DE3247869A1 - SUBSTANCES CONTAINING PHOSPHORUS CHAINS - Google Patents

Description

The invention relates to substances and materials with linked phosphorus atoms, their production and their use. The invention also relates to semiconductors and other devices using these materials. Substances and materials with chained phosphorus atoms in the context of the present description include polyphosphides with a high phosphorus content (that is, phosphides _P which by their nature remain polymers), alkali metal polyphosphides, monoclinic phosphorus and new phosphorus modifications. The phosphorus substances and polyphosphide substances are produced by vapor transport reactions in crystalline, polycrystalline and amorphous form in substance, in the form of thick or in the form of thin layers and films. Arc evaporation processes and chemical precipitation reactions from the vapor phase are used to produce thin layers. Solid-state reactions are used to

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The main crystalline semiconductors that do not contain silicon are single crystals of GaAs and GaP and InP

BATH ORIGINAL

- -er -

- ife-

Production of monocrystalline and polycrystalline polyphosphides used. To increase the electrical conductivity The diffusion doping method can be used for the materials. Rectifier junctions are produced by appropriate metal contacts on the materials. Thin layers of the phosphorus materials in question can serve as optical coatings and remuneration. Crystal powder and amorphous modifications of the materials serve as flan-resistant fillers. The crystalline forms of the materials, especially in fibrous form, can be used for reinforcement, especially for Improving tensile strength, used in plastics.

During the last few decades the use of semiconductors has become more widespread and important. For example, silicon-based semiconductors are the basis for a variety of different devices, for example for junction pn junctions with rectifying effect (diodes), transistors, controllable silicon rectifiers (SCR), photoelectric cells or photosensitive Diodes. The high cost of producing the required crystalline silicon and the increasing demand for semiconductors for an ever-expanding field of application have created the need to broaden the range of useful semiconductor materials.

The technically useful semiconductors of the invention have one Band gap in the range of approx. 1 to 3 eV (more precisely 1.4 to 2.2 eV); a photoconductivity ratio of greater than 5 (more precisely between 100 and 10,000); a specific electrical conductivity in the range of approx. 10 ~ to

- 1 2 - 1

10 (ohm cm) (more precisely, a specific electrical

—8 —9 —1

see conductivity in the range of 10 to 10 (ohm. cm));

3247 & 69

and a chemical and physical resistance below Operating conditions under normal ambient conditions. Even if numerous materials that are neither considered pure Metals can still be classified as pure insulators, as semiconductors, only such semiconducting materials can also be used as technically usable semiconductors be regarded in the sense of the invention, which meet the criteria mentioned above.

In view of the demand for the opening up and development of alternative energy sources that are independent of petroleum, The potential commercial importance of a semiconductor increases sharply if the semiconductor material can be used at the same time Has photoelectric characteristics, i.e. is able to use solar energy with a convert reasonable efficiency into electrical potentials.

From an economic point of view, amorphous semiconductors, especially in the form of thin layers, are in the form of semiconductors of single crystals because of the lower manufacturing costs for the amorphous layers. Also show amorphous Semiconductors as opposed to polycrystalline semiconductors made of the same material when used in a wide variety of Semiconductor components have more favorable electrical characteristics.

For the reasons mentioned, the semiconductor industry has been an intensive search for new semiconducting materials prescribed beyond the area of crystalline silicon.

As are crystalline non-silicon semiconductors especially single crystals of GaAs and GaP and InP as

semiconducting substances introduced into commercial practice.

Many other semiconductor materials are also used for special applications have been used. Be like that for example, CdS and selenium are used as photoconductors in many copiers.

In the context of the present specification, the term "semiconductor element" means a product, and indeed inclusive of the bare semiconductor material, independently whether this product has or needs electrical contacts, for example an electronic one Component, or is to be assigned to a non-electronic area, for example one in copying technology The photoconductor used is a fluorescent phosphor or a phosphor on the screen of a cathode ray tube.

Although it is known per se that some phosphorus modifications are semiconducting, most phosphorus substances are easy to oxidize because of their chemical instability and high responsiveness has not found any practical application as a semiconductor. No known modification of phosphorus has so far been successful - than it is commercially viable Semiconductors have been used.

Of the substances disclosed below are the III-V semiconductors such as gallium phosphide and Indium phosphide with its tetrahedral configuration can be clearly distinguished. In particular, the semiconductor These III-V semiconductors are not determined by phosphorus-phosphorus bonds, i.e. the electrical conduction in them Materials does not take place or at least not primarily along phosphorus-phosphorus bonds.

Furthermore, hydrogenated phosphorus is known to have a structure similar to that of black phosphorus and is semiconducting.

A working group headed by HG von Schnering has done considerable work in the field of polyphosphides with high phosphorus concentrations. The reports from this working group show that the highest member of the phosphorpolyxneren polyphosphides that this working group could represent? is a crystalline MP ₁₅ , where M is an alkaline earth metal. These polyphosphides are made by heating the metal with phosphorus in a sealed ampoule. In Schnering's publications, the polyphosphides are to be understood as substances with atomic bonds in the classical sense due to their crystal structure. The publications state that, in other words, the substances are or should be insulators or semiconductors, but do not show metallic conduction behavior.

The monoclinic phosphorus, also known as Hittorf's phosphorus, is produced according to the prior art from white phosphorus and lead as follows: 1 g of white phosphorus and 30 g of lead are slowly ^{melted in a closed tube by heating to 630 °} C. and then held at this temperature for a short time. The solution is then cooled at a cooling rate d of 1Q ° / in the course of 11 days up to 520 ⁰ C and then quenched rapidly to room temperature. The product obtained is then electrolyzed in a solution of 2 kg of lead acetate in 8 l of 6 percent acetic acid, the phosphorus being caught and collected in a watch glass placed under the anode. In this way, almost square plate-shaped crystals are obtained.

- Io -

their dimensions in the range of approximately 0.2 mm × 0.2 mmx 0.05 ram.

The crystal structure of this well-known monoclinic phosphorus modification was determined by Thurn and Krebs. The unit cell consists of two layers of pentagonal phosphor columns, which are all aligned parallel to one another and a second pair of layers on these two layers pentagonal phosphor columns that are generally parallel to one another, the columns in the second pair of layers being perpendicular are arranged to the phosphor columns in the first pair of layers. In the analysis of the crystal structure, the Space group, which determines the bond angles and the bond distances. The summary of this prior art is found in the "Phosphorus" section of the 1974 book "The Structure of the Elements" by Jerry Donahue.

on the electrical properties of the crystals of the Hittorf's See Phosphors, no publications appeared. This is probably due to the fact that the dimensions are only small available crystals can hardly be measured electrically.

The production of high-purity phosphorus with a quality grade corresponding to electronic requirements is according to the Prior art an unusually complicated and time consuming process, so that phosphor with electronic Quality is extremely expensive.

In the prior art, however, there is also a need for stable phosphorus compounds, in particular can be used as flame retardants and flame retardants. the Crystalline forms can also be used to reinforce plastics, glasses and other materials will.

- -f-s _

The invention is based on the object of new semiconductor materials to create phosphorus-based.

This task is accomplished by a class of new alkali metals— polyphosphide dissolved, the exploitable semiconductor properties ,, have optical properties and mechanical properties.

A “polyphosphide” is within the scope of the invention understood a material whose characteristics are determined by multiple phosphorus-phosphorus bonds. Under a In the sense already set out above, “nutable semiconductor” is understood to mean not just a material whose specific electrical conductivity lies in the intermediate area between an insulator and a metal, but rather a material that also has a variety of other usable characteristics and properties:

- stability

Elastic material structure

Band gap in the usable range (typically 1 to 2.5 eV)

high specific electrical resistance, but dopable

- good photoconductivity
Luminescence with good efficiency Possibility of forming blocking bar transitions, in particular for rectification purposes, producible at relatively low temperatures (for semiconductors) by a process that can be carried out on an enlarged scale for industrial production

Ability to form larger, thin, amorphous layers

- Possibility of forming flexible polymer fibers,

The polyphosphides that are the subject of this patent application are now surprisingly materials, all of them have the features mentioned above.

Equally important is that the useful properties of the material over a wide range of chemical Composition and physical modification (crystalline and amorphous) are retained.

As far as the applicant is aware, the polyphosphides are the only practically usable semiconductors in which The characteristics measured in the single crystal are retained even in the amorphous state of the material. This is why of great technical importance because the amorphous modifications are usually more easily accessible. This feature is also important for applications with larger-sized devices, for example photoelectric cells, large display screens, and electrostatic copiers.

The main problem that has arisen in the prior art so far Opposing the extensive use of amorphous semiconductors is that with the known materials not or not a stable single-phase material can easily be produced. However, even if the amorphous material is single phase can be produced, the loss of important characteristics must usually be accepted in such amorphous materials showing the single crystal phase.

The most important known semiconductor, silicon, has a crystal structure with tetrahedral coordination. Everyone Attempts to produce amorphous silicon have so far always led to the breaking of the tetrahedral-coordinated bond structure, resulting in unsaturated valences occur that affect the semiconductor properties of silicon

decisively unfavorable influence. Pure amorphous silicon is technically worthless. It's unstable and crumbly. Attempts to saturate the unsaturated valences of amorphous silicon with hydrogen or fluorine are so far only

been partially successful.

It must be assumed that the integrity of technically interesting and useful properties the polyphosphides is directly attributable to the structure of these materials, which in turn is ückzufuhren to the very specific properties and the very specific behavior of phosphorus to "", in particular namely its ability to Formation of polymers which in the vast majority of all phosphorus sites in the lattice are characterized by three covalent phosphorus-phosphorus bonds.

In crystalline form, the polyphosphides have the type
MP ₁₅ (with M = Li, Na, K, Rb, Cs) has a structure that consists of a phosphor framework of parallel phosphor columns with a pentagonal cross-section »This
Phosphor columns with a free inner channel are in the
FIGS. 4, 5 and 6 linked to one another via PMP bridges. The assembly for this atomic MP., ..- framework can be a P _o structure (composed of two rigid P ₄ assemblies) and an MP _? -Module
(formed from a rigid MP ₃ assembly and a P 1 assembly).

On the basis of the assemblies or clusters described above, Kosyakov (Russian Chemical Review, 48_ (2), 1979) has theoretically shown that the polyphosphides can be regarded as polymers in which the basic assemblies can be regarded as monomers. It should therefore be possible, at least in principle, to have a large number

to build atomic structures with the same phosphorus skeleton.

The applicant has during the work on the present invention by a variety of methods described in more detail below MP ₁₅ crystals as well as substances of the type (MP.) -, synthetically prepared (P _Q), wherein the

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Parameter b is much larger than parameter a. These new substances high in phosphorus are original in the form of "fibers", "whiskers" or "ribbons" and are within the scope of the present specification Exercise referred to as MP, where the parameter χ a

Ji

Has a value significantly greater than 15. These materials with a low metal concentration are produced by transport reactions via the vapor phase in the form of thick layers (larger than 10 μπ made of polycrystalline fibers) and large spheres (with a volume of larger than 1 cm) with an amorphous character. The polycrystalline fibers show the same morphological behavior as the KP _1g whiskers.

The structure of the first crystalline MP material (x very much larger than 15) that the applicant was able to produce is determined by a phosphor structure which is similar to _{the phosphor structure of the MP 15 "substances.}

Measurements have shown that the usable electrical and optical data of the crystalline materials MP ₁₅ and MP (with χ much greater than 15) are similar and

are comparable. The properties of these materials are therefore determined by the numerous covalent PP bonds of the phosphorus structure, this phosphorus structure having a coordination number of slightly less than 3. Surprisingly, however, the applicant has found that the utilizable electrical and optical properties of these materials, namely for MP ₁₁ . and MP (with χ much larger than 15), which are in the crystalline

■ - ar -

Material are present, are also retained in the corresponding amorphous material.

In contrast to other well-known materials in this case there is namely a rigid one-dimensional structure, which is only explained in the following Meaning can be described as elastic. The crystal symmetry of the polyphosphides is quite low (triclinic). Obviously, this slightly symmetrical material is at the transition from the crystalline to the amorphous structure able to cope with the increasing structural disorder that characterizes the amorphous state to accommodate adaptively. In this transition there is no ripping or tearing strong tetrahedral bonds (coordination number 4) as in silicon, since the phosphorus with its essential lower coordination number compared to silicon can absorb greater structural disorder without doing so to form unsaturated valences. The polyphosphides are polymer by nature. An amorphous polymeric structure is thus obtained in the conversion, which no detectable maxima in the X-ray diffraction spectrum shows »Nevertheless, the local organizational structures are sufficient wider than is the case in conventional amorphous semiconductors. All observations suggest that in the transition from the crystalline to the amorphous phase in the polyphosphides, a gradual one in the structural sense The onset of the amorphous state occurs, this gradual onset and entry into the The amorphous state is the reason for the retention of the properties and characteristics observed in the crystalline material is also in the amorphous state of the polyphosphides.

The chemical composition and structure of the polyphosphide family clearly distinguishes these substances of all known usable semiconductors;

BATH ORIGINAL

Group 4a (crystalline Si, amorphous Si: H, etc.)

3a-5a (HI-V) (GaAs, GaP, InP, etc.)

2b-6a (II-VI) (CdS, CdTe, HgCdTe, etc.) Chalcogenides

1b-3a-6a (CuInSe ₂ )

The alkali polyphosphides (MP, M = Li, Na, K, Rb, Cs; with

■ tv

χ = 15 and χ much larger than 15) are characterized by a particularly high phosphorus content. Substances with particularly large values for χ are almost pure phosphorus. Nevertheless, due to their crystal structure, these substances are also pentagonals that are parallel to one another Columns or tubular columns) and their properties (chemical and physical stability, band gap, specific electrical conductivity, photoconductivity) clearly different from all known phosphorus modifications (black, white / yellow, red and violet / Hittorf) * - the. The structural relationships among these various modifications are detailed below discussed.

Through the applicant's work on the polyphosphides Much light has also come into the relationships with phosphorus itself. Daih ~ misunderstandings often occur in practice arise due to inconsistent nomenclatures, the nomenclature used here is reproduced below:

1. Amorphous phosphorus or red phosphorus

Amorphous red phosphorus is a generic name for all non-crystalline modifications of red phosphorus, which are commonly used made by heat treatment of white phosphorus will.

V:

2. Purple phosphorus

This microcrystalline form of red phosphorus is made from pure batches of phosphorus, either white or amorphous red phosphorus, produced by extensive heat treatment,. -. ■ ·

ο Hittorf'sc her phosphorus ■ -. -. '"

Crystalline form of red phosphorus and structurally identical to purple phosphorus. Hittorf's phosphorus is produced in the presence of a large surplus of lead. Despite these differences, the terms "Hittorf's phosphorus" and "violet phosphorus" are often used interchangeably. The crystal structure consists of double layers of parallel pentagonal hollow columns with adjoining double layers , in which the phosphor columns are arranged perpendicular to the phosphor columns of the previous layer, the unit cell being monoclinic. The Hittorf's see phosphor crystals are somewhat larger (about 100 µm) than the microcrystals of violet phosphor.

4. Large monoclinic phosphor crystals

Even the large phosphor crystals with axes in the range of a few millimeters essentially point have the same structure as the two crystalline forms of phosphorus described above. These phosphor crystals, described in more detail below, are new crystals in nature and are made by Transport via the vapor phase ("VT") made from batches of alkali metal phosphorus. The inclusion of Alkali is evident for the formation of the

- 4-4- -

large crystals essential. Chemical analysis confirms the presence of alkali metals iii such large phosphor crystals in concentrations of 500 to 2000 ppm.

5. Twisted phosphor fibers

A crystalline form of phosphorus described in this document and obtainable from an amorphous phosphorus charge by a vapor transport reaction ("VT treatment"). This form of phosphor has practically the same structure as the polycrystalline MP _v "ribs".

The many allotropic forms of elemental phosphorus are proof of the diversity and complexity of the bonding relationships and structures that make up phosphorus can assume or which are accessible with phosphorus, about the exact mode of action of the alkali metal in the Nothing is known about the development of the individual phosphor structures at the moment, but the ones that are available up to now are not Data indicate that the alkali metal stabilizes phosphorus in such a way that a single one at a time Structure selected and stabilized from the variety of potentially possible and available structures will.

Without the presence of at least some alkali metal, the following undesirable phenomena are observed:

A) The phosphorus is unstable (e.g. white phosphorus).

B) To the extent that phosphorus is at all as one If fiber can be present, it can only do so at high temperatures and with one from the range of microcrystals limited grain size (e.g. purple phosphorus), or

CJ at high pressure (e.g. black phosphorus).

D) Without the presence of alkali metal in a particular batch, the MP structure is not evolved by vapor phase

dft

transport reaction formed. Instead, the phosphor is obtained in the form of twisted fiber _t which has been found through the work of the present application. However, this crystalline phase is metastable and the structure is not particularly well developed, as shown by the X-ray diffraction spectra, the Raman spectrum and the photoluminescence data.

Due to the presence of alkali metal during the vapor phase transport reaction the formation of strictly parallel, untwisted phases is encouraged. Under these conditions, the Formation of large monoclinic phosphor crystals favored at different temperatures.

The predominant role of the structure and not the composition as the decisive determinant of the properties of the substance can be seen from the fact that KP (x much greater than 15) has properties (band gap, photoluminescence, Raman spectra) which essentially correspond to the data of KP ₁ - correspond, however, to the corresponding data for monoclinic phosphorus.

It should be emphasized that even the smallest amounts of alkali metal of choice can serve to form stable phosphor phases. However, the question remains whether other elements can also do this,

ν Ί '/ "]"': '/ 324786?

that are not alkali metals. Krebs reports on alkali metal-free polyphosphides with hollow column structures of the formula 2b-4a-P ₁₄ (2b = Zn, Cd, Hg and 4a = Sn, Pb). How do these structures come about?

It would be conceivable that with these substances the hollow column structure is formed because the element of the fourth main group of the periodic table of the elements is amphoteric and can replace phosphorus atoms on phosphorus sites.

On the basis of the ionization energies of the alkali metals, which are all equal to or less than 5.1 eV, the apparent electron affinity in the P ₁ , .- lattice, or better P. _c -part-

Ib Id

grid, calculate. With these results you can then also calculate the apparent ionization potentials for the other possible compositions, for example so also for the 2b-4a-P ... substances. All substances of this Group of materials examined by Krebs show apparent ionization potentials of less than or at most equal to 4.8 eV.

The present invention is based on the initial finding that KP ₁₅ whisker single crystals are stable semiconductors with a band gap of 1.8 eV in the red range and have both photoconductivity and photoluminescence with sufficient efficiency. These data are characteristic of semiconductors that are potentially suitable for practical use in the field of electronics and optics. The whiskers of the other MP .., substances containing alkali metals also have these characteristics (M Li, Na, Rb, Cs).

The prerequisite for recognizing the potentially usable features was the ability to manufacture these materials in geometric dimensions and shapes that the

Production of corresponding elements and test items made possible. In attempts in this direction it quickly became apparent that the habit of the crystals was not particularly good suitable for pulling large single crystals, especially not for growing single crystals that are free from twin formation »" genes are “Such large, twin-free single crystals are, however, the basis and prerequisite for practically everyone Semiconductor components that can be used and used in technology today. Polycrystalline materials are less common suitable because they are even with a relatively large grain size individual crystallites have grain size influences, the physical and chemical discontinuities of which are usable Adversely affect the characteristics and properties of the crystalline material. The applicant has her attention For this reason, the amorphous phases of these materials are increasingly turned to.

Practically usable amorphous semiconductors that act as blocking elements for example in the form of photoelectric cells or as a coating material in electrostatic copiers are used, have so far mostly been produced in the form of thin coatings, due to the fact that they are foreign to the material Influences (cost, convenience of manufacture or requirement of the application geometry) as well material-related reasons (material problems more general Type in larger solid bodies of a material in the amorphous state).

Research in this direction initially showed that KP ₁₅ can be produced as a thin, stable amorphous layer by vapor phase transport reaction. This is not the case for silicon, for example, since amorphous silicon, in contrast to silicon single crystal, is not stable.

-hl -

In the vapor phase transport reaction, KP (χ much larger than 15) is also larger in the form of stable amorphous Pieces and sturdy amorphous thin films available.

These polyphosphides also show unusual behavior in other respects. The usable properties of the materials MP _1f - and MP (x much greater than 15), which are found in the crystalline state of the materials, can be found almost unchanged in the corresponding amorphous forms (see Tables XVI and XVII below).

Applications for the thin amorphous KP ,. ₅ layers that do not require barrier transitions are obvious (e.g., electrostatic copying). The application in systems that do not require a barrier layer transition is all the more interesting because KP ₁ ς has a specific electrical resistance of around

8 9 10 to 10 ohm cm.

Electronic and optoelectronic components generally require the formation of barrier layer junctions either in the particular material or with the material to have a sharp limited discontinuity in the course of the potential To create energy that is scanned by the charge carriers migrating in the material. This requires a decrease in the specific electrical resistance of the material due to doping.

By diffusing nickel into KP ₁₅ , the specific electrical resistance of the material can be reduced by several orders of magnitude. Surface analyzes have shown that nickel diffusion from the solid state (deposition of a KP.-j. Layer on a nickel layer) follows the normal diffusion pattern during the growth of the precipitation layer.

Component configurations with nickel as carrier contact and doping source and other metals such as
Cu, Al, Mg, Ni / Au, Ag and Ti as contact metals on the

opposite (upper) surface lead to the formation of a barrier layer. The current-voltage characteristics across the junction of such devices are for the above metals mentioned as acceptance contacts on the top of the component carried on the Mickelschicht measured been. The capacity-voltage characteristics of such transitions have been measured with Al and Au as the upper contact metals. The data allow the formation of double barriers detect a high-resistance layer in the area of the upper contact.

This high-resistance © surface layer is undoped
Zone of KP ₁ . , .- Layer / its formation -single is a consequence of the doping process used up to now.

In addition, there is a not very significant photoelectric effect with currents in the microampere range under short-circuit conditions observed.

The following are methods of making the polyphosphides with different compositions and. morphological

Characteristics described.

A. Condensed Phase Synthesis (CP)

This means a process in which an initial charge is first heated isothermally, then tempered at a constant temperature and then cooled again, this heat treatment being carried out in a container with the smallest possible volume. Under these conditions there is practically no transport via the vapor phase. According to this process ("CP") crystalline and polycrystalline MP _{15 is produced} in bulk.

I /

B. Synthesis by Vapor Transport Using a Single Source (1S-VT)

The starting reaction mixture is arranged in a zone of an evacuated tube which is heated to a temperature Tc that is greater than a temperature Td, where Td is the temperature or temperatures of one or more other zones of the evacuated tube where the target product is precipitates from the vapor phase. This process can be used to produce: Crystalline MP ₁₅ ; crystalline, polycrystalline (in substance and in the form of thin layers) and in substance amorphous MP with large values for X; monoclinic phosphorus; star-shaped fiber material; and twisted phosphor fibers.

C. Synthesis by transport via the vapor phase below

Use of two different sources (2S-VT)

The starting substances with which an evacuated reaction chamber is charged are physically separated from one another, the precipitation zone for the product being arranged between the two swelling zones. The two sources are heated to temperatures which are greater than the temperatures of the precipitation zone in order to obtain at least amorphous material; (see below). The precipitation zone need not be the coldest zone in the system, but the coldest zone in the reactor should only be able to condense a single component of the vapor phase. 2S-VT was the first process used to manufacture thin amorphous layers of KP ₁₅ . Polycrystalline and amorphous thin films of MP ₁ ^ and thin polycrystalline films and amorphous substance of MP with high x values can be produced in this way.

B 4

- US

D. Quenching from the melt

An exit batch is sealed in a

and heated evacuated tube (isothermally possible) -, and to a temperature which is higher than the endothermic one determined by differential thermal analysis

Melting point - the feed is held at this temperature for some time - then the The tube is removed from the oven and rapidly cooled. In this way a CsP glass has been produced »

E. Flash Evaporation

The powdery feed material is taking slowly
pouring argon into a receiving vessel that
is heated with high frequency in the range of radio frequencies »The temperature of the collecting vessel is
greater kept at temperatures than about 800 ⁰ C.
The deposited material is inside the vessel
guided through a labyrinth, in which at least theoretically it comes into contact with the hot surfaces. The charge should be evaporated quickly and completely in such a way that the resulting steam flow has the same composition as the powder applied o The steam flow is then evacuated Chamber in which it meets colder surfaces on which the product condenses. In this way
amorphous layers are available.

^F ° Chemical corsetry reaction from the vapor phase (CVD)

This term is generally used for a process for the production of materials in which at least two starting components are mixed in the vaporous state in which they are to chemically react with one another to form the target products. So applicants have K and Ρ _Λ

- 2ΤΓ -

-Uf, -

given independently of each other and dosed in ovens, where they evaporated quickly and surrounded by a stream of argon cooler zones of the reactor were taken along. There the substance beat the mixed together Steam flows as chemical reaction product and target * product in the condensed phase.

The importance of the precipitation from the vapor phase after chemical reaction in the vapor phase (CVD) is that this process is ideally suited for the industrial scale and for doping in situ, i.e. for doping the target product at the same time as its production. _{According to this method, thin KP 1} ^ layers were produced within the scope of the experiments carried out here.

G. Precipitation from a Molecular Stream (MFD)

This vapor phase transport process is a process in which the starting substance is vaporized from several sources and essentially a combination of the process type 2S-VT and an epitaxial growth from a molecular beam ("MBE") corresponds. Independent Heated evaporation sources are used to evaporate the starting substance, the Flow of vaporized molecular particles or fragments with a flow not achievable in the 2S-VT process Way is controlled so that the molecular current also independently heated substrate in exactly predetermined Rates achieved. Precipitation takes place in an evacuated chamber, with the progression the current condensation from the vapor phase in a process of the type 2S-VT is also not achieved Way is monitored. The reaction chamber can either be hermetically sealed or used for monitoring the vapor pressure must be continuously evacuated.

A great variety of polyphosphides of various physical forms and chemical compositions were produced at the beginning of the applicant's investigations.

In the course of the work, the interest grew Reasons of practical application from single crystal growth to the production of amorphous materials both laid in substance as well as in the form of large-area thin layers ο

Among all MP ₁ materials, KP _{15 is} a crystalline material with a high phosphorus content , which in the KP system of the MP systems with x values equal to or greater than 7 is noticeable as unusual due to its characteristics «(In contrast, the other alkali metals with phosphorus only substances in which χ has the value 7 or 11, for example CsP ₇ , NaP-, RbP ...., etc.). KP ₁ . and KP_ cannot be isolated as substances of the most solid chiometry. For this reason, the KP system can be monitored and controlled more easily than other alkali metal-phosphorus systems, in which several different, stychometrically composed substances can form.

In addition, the experimental work of Applicant that in all cases in which potassium and phosphorus are evaporated, regardless of by what means or by what process this evaporation is carried out, and in a corresponding atomic evaporation ratio ([P] / [K] equal to or greater than 15) are transported into a zone, whose temperature is in the correct and nutsable temperature window, amorphous KP., ς is formed. It is the "temperature window" a temperature that is low

is enough to prevent a crystallization of KP ₁₅ and at the same time is large enough to rule out a precipitation of KP with χ much greater than 15.

Based on these findings and this teaching, it is shown that all the different synthesis processes in the case of the production of KP ₁₅ can be operated according to the same basic principle. Each of these methods uses only different means for regulating and controlling the evaporation squelIe and the regulation or control of the precipitation of the target product. The evaporation processes that work with two sources (2S-VT, CVD and MFD) can be used particularly favorably because the decisive process parameters can be controlled and regulated independently of one another.

Due to the considerations presented above, amorphous KP ₁ C in the form of thin layers has been selected by the applicant as a model substance for the development of new usable semiconductor materials in the field of polyphosphides.

The method of evaporation using a single evaporation source was investigated further the properties of the polyphosphides Potassium polyphosphide whiskers made with a length of about 1 cm. X-ray diffraction tests ensure that that the obtained and measured single crystals actually KP. ^ - crystals are. The semiconducting behavior of these whiskers is also tested. If the so produced Whiskers are exposed at 4 κ with an argon laser, a photoluminescence occurs, which when measuring a emitted energy of 1.8 eV. This value suggests

points out that a band gap in precisely this energy range is to be expected for the material under investigation.

To measure the specific electrical conductivity of these whiskers, electrical connecting wires are attached with silver contact pastes »The secure contact between the supply lines via the silver paste to the crystal is microscopically monitored during the conductivity measurement» This surprisingly shows that when the monitored crystals are moved in the microscope and thus different electrical conductivities can be measured when the exposure of the crystals changes. Accurate measurements have shown a photoconductivity ratio of 100, while the specific electrical

—8 Conductivity of the unilluminated whiskers about 10

(Ohm cm). To determine the band gap of the whisker material, the specific electrical photoconductivity as a function of the wavelength, the optical absorption as a function of the wavelength and the temperature dependence of the specific electrical conductivity of the whiskers are then measured. All of these measurements confirmed the photoluminescence measurements at 4 K that the whisker material had a band gap of approximately 1.8 eV. In this way it could be ensured that the KP ₁ , - "" whisker crystals belonged to the group of potentially usable semiconductor materials. _{During the manufacture of the KP 15} whiskers, an amorphous coating is formed on the inner wall of a quartz tube by vapor phase transport. A band gap on the order of 1.8 eV and a photoconductivity ratio on the order of about 100 are also measured for this amorphous layer. Like the crystalline whiskers, the amorphous layer has a specific electrical conductivity of approximately 10 (ohm · cm). In this way it could be verified experimentally that the amorphous

-ευ -

Material is an at least potentially exploitable semiconductor material.

The applicant then asked himself whether KP _{15 could} also be grown in the form of larger single crystals such as silicon and whether it would be amenable to the production of semiconductor material in this form. It was also investigated whether polycrystalline or amorphous layers of KP _{15 could be} reproducibly produced and whether they would be suitable and usable for the production of semiconductors. Then the material produced during the vapor phase transport tests had to be precisely analyzed and identified and the question had to be clarified whether analogous materials would also have the same practically usable characteristics.

After numerous attempts at vapor phase transport, the applicant then found with astonishment that the substances obtained from only one single evaporation source containing potassium and phosphorus in a mixture with one another, that by heating the source and condensing the reaction product from the vapor phase at the other end

* of a closed reaction _{tube did not correspond to the composition KP 15} , but corresponded to the composition KP on the basis of the chemical wet analysis carried out, whereby

χ according to the wet analysis results in the range of approx 200 up to about 10,000.

The subsequent intensive systematic investigations by the applicant have led to the surprising result that the affinity of phosphorus for potassium or any other alkali metal in vapor phase transport reactions using a single evaporation source leads to the initial precipitation of MP ₁ C as the most stable polyphosphide. In the presence of excess phosphorus, however, a condensate forms

* were obtained

new form of phosphorus "=., corresponding to the chemical composition MP with x values of much greater than 15. Surprisingly, these new forms of phosphorus have the same electronic characteristics and qualities as KP ₁₅ and, overall, can be classified as valuable semiconductor materials.

The intensively carried out attempts to produce thin layers of polycrystalline and amorphous KP .., - and the analogous substances with other alkali metals have shown that such layers could not be produced if the starting substances mixed with one another to carry out the vapor phase transport reaction from a single evaporation source evaporated. For this reason, the applicant has developed a method for synthesizing the substances by means of a vapor phase transport reaction, in which the starting substances are evaporated from two separate evaporation sources. According to this process, the alkali metal and the phosphorus are heated separately from one another and independently of one another and evaporated from sources arranged independently of one another. With simultaneous control and regulation of the temperature of a thermally separated intermediate precipitation zone, thin MP ₁₅ layers in polycrystalline and amorphous form can be obtained, wherein M in the above formula can be any alkali metal. This two-source process also made it possible to produce thin layers of polycrystalline and thick layers of amorphous phosphorus material of the new form, as well as other obviously polymeric materials of the formula MP, in which M is an alkali metal and χ has a value that is much greater than 15.

The processes of extremely rapid evaporation, precipitation after chemical reaction from the vapor phase were also used and precipitation using a

BATH ORIGINAL

-JAr-

Molecular flow used to produce the materials.

To characterize all polyphosphides according to the invention, the uniform general chemical formula MP ver turns. Practically usable semiconductors are used for values

* of the parameter χ in the range from 7 to infinity. Those alkali metal polyphosphides to which the chemical formulas MP ₇ , MP ₁₁ and MP ₁₅ correspond are known. In the context of the present invention, substances of the general chemical formula MP in which the parameter χ has values of very much greater than 15 are described for the first time and are new.

Vapor phase ' transport reactions used / in which a single evaporation source is used to evaporate the starting substances serves. By regulating the precipitation temperature and, in particular, by keeping the precipitation temperature constant However, these processes, which are known in principle, are decisively improved over larger areas of precipitation. Through this can also use large-area thick layers and spherical substances in polycrystalline and amorphous form with the chemical Composition MP are obtained in'den χ values of much greater than 15.

Large amounts of crystalline and polycrystalline material of chemical composition MP ₁ c, where M is an alkali metal, have been produced in such a way that stoichiometric proportions of alkali metal and phosphorus were mixed with one another and heated isothermally. This process for the production of condensed phases leads to excellent material of the composition MP with values of the parameter χ in the range from 7 to 15. This process can be carried out well in vapor phase transport reactors with an evaporation source. This can make this process more effective

obtain

. sz -

that the alkali metal and the phosphorus are homogeneously mixed with one another and ground in a ball mill before the evaporation source is charged. The ball mill is preferably turned on for mixing. Temperature in the range around 100 ⁰ C heated. In this way, surprisingly, relatively stable powder mixtures are obtained.

The product investigations have shown that all polyphosphides with structures that are characterized by parallel hollow columns, band gaps in the range of 1.8 eV, photoconductivity ratios of much greater than 5 with measured ratios in the range of 100 to 10,000 and a low conductivity in the range of 10 to 10 ~ ⁹ (ohm · cm).

It turns out that the amorphous forms of all these materials, i.e. the alkali metal phosphide MP with x-values of greater than 6 formed in the presence of an alkali metal, at least substantially equal semiconductor properties on v / ei s en, so that the conclusion is obvious that the short-range order of the amorphous materials of the short-range order which resembles crystalline materials and is essentially characterized by parallel pentagonal tubular columns the total area of the amorphous phase are marked.

In all polyphosphides dominate and determine the three covalent homoatomic phosphorus-phosphorus bonds on the the vast majority of all phosphorus sites the electrical conduction paths through the structure and are much more important than all other bonds, the phosphorus-phosphorus bonds establishing overall semiconductor properties.

All phosphorus atoms of the material that are cross-linked and linked to one another by covalent bonds form

together the predominant electrical conduction path through the material, whereby the parallelism of the Alignment marked crystalline short-range regions give rise to the good semiconductor properties give. The phosphorus atoms are trivalent in these structures, whereby the concatenation of the atoms leads to the formation of Spirals or columns with an internal hollow channel leads. The alkali metal atoms if these are in the structure exist, connect the individual chain sections of the structure with one another. Atoms other than phosphorus, especially if these are trivalent and capable of forming three covalent homoatomic compounds should also be able to form semiconductors of this type.

The invention thus relates to new forms of phosphorus and processes for their production, solid layers of amorphous or polycrystalline MP and processes as well as a device for their production, process and device for the production of metal phosphides by vapor phase transport processes with several controlled temperatures using a single evaporation source, process and device for the production of polyphosphides with a high phosphorus content by vapor phase transport using several separate evaporation sources, method and device for the production of MP ₁ C in polycrystalline form by solid-state reactions, semiconductor components, the polyphosphide groups with at least them "ben covalently linked to each other and in Contain phosphorus atoms arranged in pentagonal hollow columns and have a band gap of greater than 1 eV and a photoconductivity ratio in the range from 100 to 10,000, semiconductor components Ments containing a substance of the composition MP in which M is an alkali metal and χ is greater than 6, and materials with band gaps greater than 1 eV and photoconductivity ratios of 100 to 10,000, semiconductor components made from a

Material that has very large proportions of a chain cross-linked covalently bonded trivalent atoms, preferably phosphorus atoms Containing material consists, in which the chain-linked atoms by several covalent bonds with each other are linked and have a short-range order, which contains layers of chained atoms in each of the layers are arranged parallel to one another and wherein the layers are also mutually parallel to one another are arranged, - and the concatenations are preferably pentagonal Form hollow columns, Kalbleiterbauelemente that a Alkali metal and the aforementioned chained structures contained in which the number of consecutive covalent chained bonds so sufficiently larger than the number of those not in the chain Bonds is that the material is semiconducting, semiconductor components, made up of compounds that contain at least two chained assemblies, each of which is a Framework of at least 7 covalently linked atoms, preferably phosphorus atoms, and alkali metal atoms exists that electrically conductively connects the framework of a structural unit with the framework of another structural unit, barrier layer components, Process for producing such semiconductor components, processes for doping such Semiconductor components, processes for conducting an electrical current and finally processes for generating electrical currents Potential differences using such devices.

The fundamental idea that is essential to the invention is therefore to create a new substance class of valuable semiconductor materials to create or make available, within which a part of the individual connections is new and here for the first time is described, while another part of the substances included in the class is already known per se, but not as technically applicable and exploitable

BATH ORIGINAL

Semiconductor properties endowed substance has been recognized.

All of these materials have a band gap in the range from 1 to 3 eV, preferably in particular in the range from 1.4 to 2.2 eV, especially preferably around 1.8 eV. The photoconductivity ratios are values of greater than 5, actually in the range between 100 and 10,000. The specific electrical conductivity these materials range from about 10 to

- 12-1

10 (ohm * cm), so it has an order of magnitude in the range

_Q ..I

of 10 (ohm cm)

On the basis of the present description, the person skilled in the art will readily recognize that the alkali metal component M of the poly ~ phosphides or other corresponding trivalent "ide" capable of forming homoatomic covalent bonds and correspond to the general chemical formula MY, may contain a number of alkali metals, including combinations these may contain metals that have a binding behavior corresponding to the binding behavior of the alkali metals can "pretend" and contain these metals in any proportions, without the basic to change the pentagonal hollow column structure and without doing so to significantly influence the electronic semiconductor characteristics of the material.

The invention also provides a method for doping the Materials according to the invention with iron, chromium and nickel to improve the specific electrical conductivity of the substances. Contact barriers were made using Al, Au, Cu, Mg, Ni, Ag, and Ti made and measured by silver contact paste and point probes.

The incorporation of arsenic in the polyphosphides with each other parallel hollow columns also leads to an increase in the specific electrical conductivity.

Also these methods for doping the semiconductor material are part of the present invention.

The semiconductors and the devices and components of the invention can be used in a variety of ways. The following are areas of application for the materials of the invention? Photoconductors, especially in photocopiers? Light emitting diodes? Transistors, Diodes and Integrated Circuits © ° _t Photoelectric Applications? Motalloxid-Balfo circuit elements? optical sensors and scanners? Phosphors for excitation by photons or electrons as well as numerous other semiconductor applications =

In the context of the present invention, the applicant has also produced large monoclinic phosphor single crystals for the first time. These crystals are obtained by the vapor phase transport technique, and swa? starting from MP ₁ "feeds or feeds in the form of mixtures of M and P with many variations in the concentration ratio (MP). Surprisingly, these large monoclinic phosphorus single crystals contain considerable proportions of alkali metals (500 to 2000 ppm were observed). Under the same conditions, these crystals cannot be grown because there is no alkali metal in the charge.

For these large crystals of phosphorus there are two different ones

Crystal habit observed =

The crystals of one habit have the truncated pyramidal crystal shape shown in FIG. 39. These crystals are particularly difficult to split »The other habitus

Sad original

• * «Ρ 1.

- 58 *

corresponds to the platelet-shaped crystal formation shown in FIG. 40, which is easily cleavable.

The largest crystals were grown in the habit shown in Fig. 39 and had dimensions of the order 4mm x 3mm x 2mm (height). The largest crystals that could be obtained in the habit shown in Fig. 40 are roughly square, have an edge length of about 4 mm and a thickness of 2 mm.

The crystals have a metallic appearance in the reflection and are dark red in the transmission. The chemical analysis shows that the crystals contain in the range of 500 to 2000 ppm alkali metal. That of polycrystalline powder samples obtained X-ray diffraction diagrams, the Raman spectra and the differential thermal analysis all show at least substantially Corresponding structures and data such as the well-known Hittorf's see phosphorus.

The photoluminescence spectrum of those grown in the presence of cesium Crystals (Fig. 41) and the crystals grown in the presence of rubidium (Fig. 42) show luminescence

-1 -1 ·

maxima at 4019 cm or at 3981 cm. Calculated from this a band gap of approx. 2.1 eV at room temperature for this monoclinic form of phosphorus.

The crystals obtained in this way can be used, for example, for the following applications: as a source of phosphorus; as optical rotators in the red and infrared regions of the spectrum, taking into account that these crystals are birefringent; as substrates for growing III-V semiconductor materials such as indium phosphide and gallium phosphide. The material of this type can be used in luminescence screens or in lasers.

The same loading batch results in a slightly smaller amount Temperature star-shaped fibrous crystals of the type shown in Figures 44 and 45 are deposited »

Finally it was carried out in addition to numerous other attempts Vapor phase transport reaction grew a crystal of an allotropic phosphorus like the one in Pig. 46 shown twisted or twisted phosphor fibers.

The polyphosphides according to the invention can be used as flame retardants and reinforcing fillers are used in plastics, as glasses and in the form of other materials. The twisted ones columnar crystals and the star-shaped fibrous crystals should particularly be used for reinforcement of composite material because they are ideally suited to create a flush connection with a surrounding material. In contrast, the crystal flakes should be able to be used with particular advantage where there are currently glass fiber disks be used.

The sheet-like materials according to the invention are than coatings and coatings because of their chemical properties Stability, as a flame retardant and as a means of optical Remuneration used.

The aim of the invention is therefore to introduce a new class of technology to create usable semiconductor materials.

Another object of the invention is to provide new methods and devices for the production of polyphosphides.

The aim of the invention is also to make new shapes more stable To create substances and materials with a high phosphorus content as well as processes and devices for their production.

The invention further aims to provide dopants and methods for doping the for such new materials To create materials.

The invention further relates to semiconductor ^{components 1} -menten in which the new materials are used.

Another object of the invention is to provide large crystals of monoclinic phosphorus.

Another problem with which the invention is concerned is the production of high purity phosphorus.

Finally, another goal is the creation of special new semiconductor substances.

The invention also has the aim to provide a birefringent material available in the red and infrared Range of the spectrum can be used.

The aim of the invention is also to create methods according to which materials with the features mentioned above can be produced.

The invention further aims to provide such methods to that effect to improve that they are more convenient to use and cheaper to carry out than the corresponding processes are state of the art.

Another aim of the invention is to create a coating material en, fillers, reinforcing material and flame retardants.

Further aims of the complex of invention go without further ado from the description below.

3247 * 69

The invention accordingly comprises one or more inventive steps, and the relationship of each of these steps to each of the other steps is described below by way of the methods and processes, by way of example, substance compositions which have certain characteristics, properties and the definition of ingredients and components which are described in the following Compositions described are exemplified, articles of manufacture with certain features , properties and the relationship of the elements , which are exemplified with reference to the objects described below and devices in which the features of the construction and the arrangement of the parts are exemplified are shown below explained in more detail using the apparatus described below.

In summary, the invention is based on the object of providing semiconductor technology with a new material to provide, whose feature profile and characteristic data profile a enables broad technical application, including in photoelectric and optoelectronic fields, as well as methods and devices for inexpensive production of the semiconductor material and the use of such material to indicate «.

To solve this problem, the invention creates a phosphorus-rich one Material as it is the subject of claim 1.

The invention is explained in more detail below on the basis of exemplary embodiments in conjunction with the drawings.

Show it:

Fig. 1 in a schematic representation and partially in section a device for Performing the vapor phase transport reaction with a single evaporation source;

3247 & 69

Fig. 2 is a schematic representation of a

Part of the vapor phase transport reactor according to FIG. 1;

3 shows a further schematic representation

simple device for carrying out the vapor phase transport reaction;

4 shows a schematic representation of the partial phosphor grid of MP ₁₅ (M = alkali metal) based on the computer evaluation of X-ray diffraction diagrams;

5 shows the partial phosphor grid of KP ₁₅ , likewise

on the basis of computer-evaluated X-ray diffraction diagrams from which it can be seen how the covalent phosphorus bonds in the arrangement of FIG Form pentagonal column structures with an internal hollow channel, wherein in FIG. 5 a cross section perpendicular to Axis of pentagonal columns is shown;

FIG. 6 is an illustration of that shown in FIG

Art, although the pentagonal phosphor columns are shown in axial section

Figures 7 and

in an enlarged representation microphotograph

phien from KP .., - crystal whiskers;

9 shows the schematic X-ray diffraction diagram

of polycrystalline KP ₁₅ ;

10 shows the schematic X-ray diffraction diagram

grams of polycrystalline KE, wöbe χ is much greater than 15;

11 a schematic representation of a reactor tube for experimental purposes for the vapor phase transport reaction with two evaporation sources;

ο 12 the temperature profile in the reactor according to

Fig. 11;

13 shows the profile of the concentration ratio of phosphorus to potassium in the in Fig. 11 shown experimental reactor;

14 shows a schematic representation of an apparatus for carrying out the vapor phase transport reaction using jswei evaporation sources;

Fig = 15 in a schematic representation of one of the

Elements of the device shown in Figure 14;

16 shows a schematic representation of a further Reaction tube for carrying out the vapor phase transport reaction under Use of two evaporation sources;

17 shows a schematic representation of a ball mill, how it can be used advantageously to implement the invention;

Figures 18, 19

and 20 scanning electron micrographs

a thin layer of a new form of phosphorus MP with χ much larger than 15;

Figure 21 is a photomicrograph of an etched

amorphous surface of such an MP material with large x-values, where the Material by vapor phase transport reactor using a single source has been made;

Figure 22 is a photomicrograph of an etched

amorphous surface of an MP material with large values for x, produced by vapor phase transport reaction using from two evaporation sources;

FIG. 23 is a photomicrograph of that shown in FIG. 22

pictured surface;

Figure 24 is a photomicrograph of an etched surface perpendicular to that in the figures and 23 surface shown;

25 is a scanning electron micrograph of the upper surface of a thin amorphous KP ₁ layer produced by vapor phase transport reaction with two evaporation sources.

26 in cross section and in a schematic representation the creation of a barrier junction;

Fig. 27

■ 44 -

a schematic representation of the on the screen of an oscilloscope for the in Fig. 26 the experiment shown occurring function curve;

Fig. 28

a schematic representation in section a further formation of a barrier layer transition on a component according to the invention;

_o 29

a representation of the oscilloscope display in the experiment shown in FIG. 28;

Fig. 30

a schematic representation of a photoresistor with an element according to the invention;

Figures 31, 32 and 33

in a schematic representation oscillographic representations of junction characteristics in components according to the invention;

Figures 34, 35 and 36

Capacitance-voltage characteristics of junction components according to the invention;

Fig. 37

in graphical representation the capacitance and resistance of a component as Function of the applied or impressed potential frequency;

Fig. 38

a schematic representation of a sealable ampoule for production of monoclinic phosphorus;

• · »■ ν ι

39 is a photomicrograph of a crystal

of monoclinic phosphorus;

4 0 is also a photomicrograph of a

monoclinic phosphor crystal;

41 shows the photoluminescence spectrum of a monoclinic phosphor crystal;

FIG. 42 is a diagram of the type shown in FIG. 41

to show the photoluminescence behavior of a monoclinic phosphor crystal;

43 shows the Raman spectrum of a monoclinic phosphor;

Figures 44

and 54 are scanning electron microscope micro

recordings of another new form of phosphorus;

Fig. 4-6 is a scanning electron microscope photomicrograph of a third new form of phosphor ;

Fig. 47 in a side view and a schematic representation of a device for immediate Substance evaporation;

48 shows a section along 48-48 in FIG. 47;

Fig. 49 shows a cross section according to 49-49 in Fig. 48;

and

- egg -

50 shows a device in a schematic representation to carry out syntheses by precipitating the product after a chemical reaction from the vapor phase,

In the figures, the same reference numerals are used as far as possible for the same parts =

The materials with high phosphorus concentrations according to the invention ₀ by way of example with reference to the high phosphorus polyphosphides MP _15, wherein M is an alkali metal, and new forms of phosphorus are described, obviously all have similar Nahordnungsstrukturen, namely irrespective of whether the substances in monocrystalline, polycrystalline or amorphous. Obviously, in the crystalline as well as in the amorphous MP ₁ , - forms, elongated phosphorus columns with an essentially hollow core are present as short-range regions, which have pentagonal cross-sections in the manner shown in FIGS. 4, 5 and 6. All these pentagonal pillars are arranged at least essentially parallel to one another in the near area, whereby MP-c double layers of the pentagonal phosphorus pillars arise in which the "pentagonal phosphorus pillars are held together by alkali metal atoms that sit on interstitial spaces. In the new phosphorus forms, the similar structures Many, if not most, alkali metal atoms are absent, but a new form of phosphorus, which is formed from the vapor phase in the presence of small amounts of alkali metal _{atoms, forms the same structure as MP 1} j-. An experiment discussed in more detail below shows that at least one form of this new phosphor can be obtained by growing on an MP.c layer, whereby the MP ₁₅ sub-punch can serve as a carrier that structurally guides the further growth of the new phosphor form

Materials that have these pentagonal phosphor columns, which are generally parallel to one another, as structural features, have a uniform band gap in the range from 1.4 to 2.2 eV, the band gaps of the overwhelming majority of the structures examined being 1.8 eV. The photoconductivity ratios range from 100 to 10,000. It is therefore becoming apparent that all alkali metal polyphosphides with high phosphorus concentrations, namely the polyphosphides from MP ₇ to MP ₁₅ and more complex forms as well as mixed polymers from MP ₁ J. and the new phosphorus forms described here for the first time (MP with χ much larger than 15), which all have the same structure of mutually parallel pentagonal phosphor columns, then, if such substances are stable, technically usable semiconductor materials become. are capable of delivering, whereby these substances would then exclude the inclusion of interfering elements, which would act as charge carrier traps, would give rise to the formation of grain boundaries or would otherwise disadvantageously change the semiconductor material.

The applicant's investigations show that in all these materials with a total of parallel pentagonal structure columns the continuously successive many covalent phosphorus-phosphorus bonds of the phosphorus columns are present in greater numbers than other bonds and therefore the primary electrical conduction path for both the electrons and the holes forms, so that basically good semiconductor properties can be expected from all substances with this structure. The investigations have also led to the finding that the presence of alkali metals in the initial weight of the starting product, even if these alkali metals are only present in traces in the new phosphorus forms described here, promote the growth of the substances in forms that are the same structural and electronic properties such as KP ₁₅ or monoclinic phosphorus

- is- -

have and maintained, depending on the conditions under which the substances are deposited will.

The group of semiconductors to which the invention is directed includes polyphosphides with a high phosphorus content, which correspond to the formula MP, in which M is an alkali metal of the first main group of the periodic table of the elements and χ denotes the atomic ratio of phosphorus to metal atoms, with χ at least equals 7. The metallic elements of the first main group of the periodic table are particularly suitable for these purposes, namely the following: Li, Na, K, Rb and Cs. Even if Fr would presumably also be suitable, it was not used in the manufacture of MP because of its rarity and because of its radioactivity. Polyphosphides with high phosphorus content, in which M is lidium, sodium, potassium, rubidium or cesium, have been manufactured and tested by the applicant.

The polyphosphides of the invention as they are within the scope of the invention must contain an alkali metal. Some of the new phosphorus forroes need smaller ones in the presence Quantities, if not immeasurably small, of an alkali metal are produced. However, this does not rule out that other metals can also be present in smaller proportions, for example those that are added in a targeted and controlled manner Doping agents or impurities.

KP ₁₅ and one of the new phosphor columns were initially in the

prepared in the manner described below.

In the manner shown in Fig. 1, one with two temperature probes Operable furnace 10 used, the outer iron jacket 12 is wrapped with thermal insulation 14, for example asbestos.

A mixture of phosphorus and potassium in a molar ratio of 12 to 1 is used as the starting substance 36. Be like that for example 5.5 g of red phosphorus and 0.6 g of potassium are introduced into a glass tube 32 under nitrogen. Before that, the Phosphorus washed repeatedly with acetone and then air dried. However, the washing process is not mandatory, but can optionally, optionally also with a different solvent, can be carried out.

After charging with the starting mixture 36, the

"4

Reactor tube 32 evacuated, in this case to 10 mbar, melted and then introduced into furnace 10. The tube 32 is arranged slightly inclined in the furnace in such a way that the charge with the starting substances 36 to be evaporated are lower than the head of the tube shown on the left in FIG Energy is applied in such a way that the temperature gradient from the heating zone 28 to the heating zone 30 ^{drops from 650 °} C. to 300 ^° C., for example. The part of the reactor tube in which the starting substances 36 are arranged is located in the area of the higher temperature zone 28.

If the furnace 10 under the mentioned conditions a sufficient has been operated for a long time, for example, about 42 hours, the supply of electric power via the supply lines 24 and 26 and the pipe 32 gradually cools down. After reaching the ambient temperature the tube 32 is opened under a nitrogen atmosphere and the contents of the reactor tube 32 are withdrawn. The reaction product is washed with CS- to pyrophoric Extract proportions. This leaves about 2.0 g of stable end product. This corresponds to a yield of approximately 33%.

When using this type of synthesis, different product phases are formed at precisely defined points
occur within the reaction tube 32 (Fig. 2). A
dark gray-black precipitate 40 in connection with
a yellow-brown film 42 typically occurs at the extreme end of the hot zone 28 where the starting mixture 36 is initially located. As the temperature progresses in the direction of lower temperatures inside the pipe 32, a black to purple-colored thin precipitate 42 is then observed at these areas 40 and 42, which is a polycrystalline material = a sharply delimited dark ring of massed crystallites 44 occurs after this precipitate layer 42 = Immediately adjacent to the crystallites 44 is a bright zone in which whiskers 4 6 have grown »This is followed by a highly reflective precipitation layer 48 , which is formed on the lower part of the reaction tube 32 at the beginning of the colder zone 30, over the precipitation layer 48 occasionally occurs a deep red
Rainfall covering 50, the occurrence of this fogging depending on the temperature, which is in the cooler
gone is maintained »The rainfall 48 and 50
can be polycrystalline, amorphous or mixed polycrystalline and amorphous, depending on the type of substances used and the temperatures set in the individual case at the outer end of the cooler temperature zone 30
a purely amorphous material 42 is found deposited as a substance or fog.

Since in the arrangement shown in Figures 1 and 2 from the hot to the cold zone in the reaction tube a continuous Temperature gradient occurs, the type of deposited material is also subject to a continuous one Change from high quality single crystal whisker to polycrystalline and amorphous material. To the better control the response and target creation

- Air -

Certain precipitation areas with larger and more uniform areas are preferred instead of the two-zone oven Three-zone furnace of the type shown in FIG. 3 is used. These <ser Three-zone furnace 54 is essentially the same as that shown in FIG. 1 and consists of an outer iron jacket 56, a refractory inner tube 60 and the reaction tube or the ampoule 58. In FIG. 3, the For the sake of clarity, the asbestos insulation of the outer jacket 56 and the insulation of the tube 58 in the 3 not shown. The furnace 54 differs from the furnace 10 in that the tube 58 is compared to the reaction tube 32 is much longer, in this case 48 cm long. In addition, the furnace 54 has three separate ones Heating zones 62, 64 and 66, which are individually controllable, so that a better defined temperature gradient over the length of the furnace inner tube 60 can be adjusted. The furnace inner tube 60 can be supported on asbestos blocks 68 and 70 and in such a way that the furnace inner tube 60 and the reaction tube 58 lying in it have a sloping towards the hot zone 62 Inclination is given in order to ensure a sufficiently good storage of the charge 36.

With this apparatus, KP _1, - whiskers obtain the best quality when set in the three consecutive heating zones 62, 64 and 66, temperatures of 550 ⁰ C, 475 ° C and 400 ⁰ C. Experiments have initially shown that voluminous precipitates obtained in furnace 10 (FIG. 1) can be obtained as layered precipitates or films 48 to 52 of the type described in FIG Reaction tube brought into the furnace inner tube 60 of the furnace 54 and heated again, but with the temperature gradient given above. The transfer of the voluminous material into precipitation layers takes place by sublimation. However, this transfer is only observed when in the hot

of the three temperature zones a temperature of at least 400 to 475 ° C is set.

_{The KP 1} single crystals produced in this way are examined with an automatic X-ray diffractometer. For this purpose, a fibrous single crystal measuring approximately 100 μm in diameter is selected and held on a glass fiber. The structure is determined with computer support from 2 ο 544 individual reflexes. All atoms of the single crystal KP, ς are determined in their exact position based on the distribution of the electron densities and a differential Fourier synthesis.

The needle-shaped single crystals obtained are further examined under high magnification in the scanning electron microscope. The scanning electron micrographs obtained of the cross-section of the single crystal needles show that these needles are apparently composed of tightly packed fibrils and not of hollow columns. Pronounced twin formations can also be seen in the photomicrographs of the KP. ^ Single crystal whiskers shown in FIGS. 7 and 8. The diameter of the primary fibrils of these whisker crystals is approximately 0.1 to 0.2 μm. Larger fibrils suggest a fine structure consisting of parallel lamellae with a thickness of approximately 50 nm each. From the first examination and analysis of the crystal structure data, the stoichiometric composition KP ₁ ^ results for the examined potassium phosphide substances.

The partial phosphor grid of this substance consists of identical Standard columns, better hollow columns, with a pentagonal cross-section. The pillars extend unidimensionally along the direction of the needle axis of the crystal. The phosphor columns are arranged parallel to each other. in the

For the purposes of a simple description of the structure, double layers of separated phosphor columns can be used which are connected to one another by an intermediate layer of potassium atoms. Due to the Measured atomic distances, the potassium atoms are at least partially ionically bound to phosphorus atoms. The cross section of a whisker is shown in FIG.

In the structure, each potassium site is assigned a rigid assembly of 15 consecutive phosphorus atoms, the have the configuration shown in FIG. Within this rigid assembly are all but a single phosphorus atom bound to each other to three other phosphorus atoms. These phosphorus atoms are chain-like with each other linked, the unsaturated bonds being related to a potassium atom in the manner shown in FIG are. The potassium atom seems to link the phosphorus columns via a missing phosphorus-phosphorus bridge. In the analyzed structure, the bond lengths from potassium to the three nearest phosphorus atoms are 0.36, 0.299 and 0.276 nm. The phosphorus-phosphorus bond lengths range from 0.213 to 0.258 nm. The bond angles in the phosphorus chains are in the range from 87 ° to 113 °, with an average of 102 °.

Arsenic forms a layered structure with a medium bond angle of 98 °, but cannot be described as a technically usable semiconductor. Also black phosphorus has a similar crystal structure with mean bond angles of 96 °. In general, however, all can be trivalent Atoms with bond angles in the range of 87 ° to 113 ° and with an average bond angle of 98 ° the same Form chain structures like the MP phases. If the bonds in the material are covalent, at least electronic properties similar to those expected for MP.

Table I shows the crystal lattice parameters and atomic positions for crystalline KP ₁₅ which the applicant has determined.

TABLE I.

Crystal lattice parameters for

Triklines system

Unit cell parameters

a = 0.9087 nm (_ + 0.015) nm

b = 1.1912 nm (_ + 0.010) nm

c = 0.7172 nm (^ 0.015) nm

= 101.4 (+ _ 0.1) °

= 107.9 (+ _ 0.2) °

= 89.3 (+ 0.1) °

The unit cell is primitive with one molecule per unit cell and a volume of 0.7233 nm. The space group is

The highest available symmetry in the structural configuration described above is a centrosymmetry of the space group P-, taking into account the given stoichiometry by KP ,, ..

9 shows the X-ray diffraction diagram for polycrystalline KP ₁ C recorded on crystal powders. The diffraction pattern was recorded with a copper tube. In the schematic diagram are on the ordinate the relative

Reflection intensities and the diffraction angle plotted on the abscissa.

Similar powder diffraction diagrams were recorded for whiskers and polycrystalline samples of MP ₁₅ with M = Li, Na, K, Rb and Cs.

All of these substances have the same structure type. In all cases, the structural framework can be considered made from one another parallel pentagonal hollow phosphor columns. These pillars are made up of phosphorus-metal-phosphorus bridges linked together.

The rigid assemblies for this structure type are P ₄ and MP ₃ . More specifically, the structural building block for the grid can be viewed as (P ₄ - P ₃ ) and (MP ₇ ), respectively.

In other words, the basic structure of the substances of type MP ₁₅ can be described as follows:

Of course, one of the subassemblies or building blocks can be present in such substances in greater numbers than the other. For example, in compounds of the type _{χ there can be} assemblies of the type (MP ₇ ) and (P _g ), which are represented in the structure in the ratio a to b. For this example, a substance MP can, for example, have the structural form (MP _n ) (P ₀ ). to express,

/ a. O O

where purely mathematically χ = (7a + 8b) / (a).

There are also substances in which the parameter b can easily be very much greater than a, such a substance still still having the same basic structure as the substances of the MP ₁₅ type described above.

Whiskers and polycrystalline "fibers" of the MP type with χ greater than 1000 (M = Li, Na, K, Rb, Cs) crystallize at relatively low temperatures of around 400 ^° C. in the vapor phase transport process. The X-ray diffraction diagrams obtained for these substances on powders essentially correspond to the data _{also obtained for MP 15.} The radiographic diffraction data obtained for KP “with χ very much greater than 15 when using a copper tube are shown schematically in FIG. 10.

If one compares the structure described above on the basis of the cross-section of pentagonal phosphor columns, the structural analogy can easily be recognized. LiP ₁₅ , WaP ₁₅ , RbP ₁₅ and CsP _{15 are of} the same structure type as KP ₁₅ . The alkali metals of these compounds assume the same function as the potassium in KP ₁₅ .

The compiled structural data clearly shows that there are countless other compounds that are known as elementary structural block in cross-section pentagonal hollow columns on iron / iron "Experiments have shown, in particular, that at least in the produced phosphorus substances and at least partially the phosphorus atoms readily against other penteles, especially arsenic, bismuth or antimony, can be exchanged. There are substitutions of up to 50 atom% possible without affecting the basic structure of the phosphorus-rich polyphosphides.

Table II shows various MP compounds which were synthesized and for which the same structure as for crystalline KP _{15 was} obtained. The data are based on X-ray diffraction images of powdery samples.

BATH ORIGINAL

TABLE II

Rigid groups MP ^ and P ₄ and

Building blocks _{lP 4} -MP ₃ ) or IMP ₇ J and [p]

Basic structure IP ₄ -MP ₇ -P ₄ J or IMP ,,.)

M: Li, Na, K, Rb, Cs

Isostructural substances with KP _-1 -

VI-X ^P "y ^P 15-y

with: 0 £ x ^

y <7.5

M and M ¹ from group 1a

P 'from group 5a (As, Bi, Sb)

While the inventors were initially of the assumption that the crystalline whiskers formed in the devices according to FIGS. 1, 2 and 3 had the same composition as the other precipitates, namely MP ₁ J- of the amorphous substances that these substances, although they _{showed the same semiconductor properties as the MP 1} , - whiskers, had stoichiometric compositions which varied in broad ranges, namely in the range from MP _{? nf)} to MP _1n nnn - surprisingly could with no variation of the three

- • 55-

Temperature zones in the furnace shown in FIG. 3 an amorphous MP ₁₅ can be produced. It was therefore found that a substantial refinement of the production process of such materials was necessary. It was therefore necessary to create new devices for carrying out the vapor phase transport process in order to enable the attempt to successfully manufacture polycrystalline and amorphous MP ₁₅ . The phosphorus-rich substances with high values for the parameter ic are, from today's perspective, preferably designated as new forms of phosphorus. They have also been manufactured according to this process after an initial precipitation of MP.c and subsequent shut-off of the alkali metal source, so that after this shutdown only the phosphorus vapor is available to re-strike in the vapor phase Approaches of MP substances are investigated in which χ has values from 7 to 15 inclusive. According to this process, the stoichiometric mixtures are heated isothermally until the reaction occurs and then cooled again. A wide variety of MP substances have been produced using this process of solid-state reaction, all of them χ

either in crystalline form or as polycrystalline powder were obtained.

The substances used for the synthesis of substances that are particularly rich in phosphorus Procedures and test methods, in particular the Recording of the electro-optical characteristics are explained in more detail below;

Applying so much energy to a system that Particles are generated, which go into the vapor phase and with the condensation or the precipitation at a certain Temperature delivering product substances is called "vapor phase transport" called. If the source material in close

Touching each other is presented and heated together

at about the same temperature, will hereinafter

from the procedure with one source or "single source procedure" for short

spoken.

The process originally described by von Schnering is essentially a single-source process of the vapor phases * - transport technology, even if the load was occasionally placed in separate ampoules, i.e. in buckets with metal filled ampoule and one ampoule filled with phosphorus. However, both loading vials were then at least heated to substantially the same temperature. The flow of vapor particles from the source to the precipitation zone however, it was effectively the same as the true single source process in which a mixture of metal and phosphorus is heated will. The principal feature of the single source vapor phase transport process is based on the fact that the vapor particles are first brought together at high temperatures and only afterwards be precipitated at a lower temperature.

The method described below, which is also based on the Schnering's method, is used for the production of the alkali metal polyphosphides according to the present invention, but provides improved results compared to the original method, in particular the possibility of a more selective production of the following materials: crystalline metal polyphosphides from Type KP ₁₅ ; polycrystalline polyphosphides with low alkali metal concentration of type KP with χ much greater than 15; and new forms of amorphous phosphorus in which the alkali metal concentration can also be less than 50 ppm.

The vapor phase transport method, revised by the inventors, has a number of features that are considered to be inventive be considered: the type of feed, the feed ratio, the length of the reaction tube, its geometry

Kt φ

as well as the profile of the temperature gradient. The following are Examples of the relationship between the temperature distribution and the precipitation of the product are described as well as the improved process for temperature control, di§ a selective Creation of specified target products Enables.

t ■ E

To carry out the procedure developed by the applicant

Pr

become an alkali metal and red phosphorus in quaiz tubes

Ii -4 melted under reduced pressure, preferably at about 10 mbar. The atomic ratio of the two elements to one another is in the range from P / M = 5: 1 to 30: 1 *, preferably in particular 15: 1. the starting elements are generally mixed together in the ball mill before they are placed in the quartz tubes. The grinding 4rfolgt in stainless steel ball mill with a Mahlverweil time of at least 40 hours' The ball mills are heated in the Rfgel for grinding to 100 ⁰ C, in order to promote the distribution of the alkali metal in the red phosphorus powder.

The aim of the grinding is to achieve intimate contact between the two elements, whereby the mixture should be as homogeneous as possible. When milled dust-fine powders are obtained which .and handled easily in a dry box can be -gelagert \ to show no noticeable change. Compared to their constituents, especially compared to the alkali metal, these ground powders show an astonishing stability when they are exposed to both atmospheric air and moisture. If, for example, water is added directly to samples of the powder, * the material will only burn at the point of application and in isolated cases. ;

Production of single crystal, polycrystalline and amorphous ^MP 15 I.

A mixture of the elements (alkali metal and red! Phosphorus) becomes

ORIGINAL INSPECTED

under reduced pressure, namely at a pressure of

-4

less than 10 mbar, fused in a quartz tube 58 (Fig. 3), which is approximately 10 cm long and a diameter of about 2.5 cm. The reactor tube 58 is in a three-zone furnace (Lindberg, model 24357) after a stored by two methods. According to one of these methods, a second quartz tube 60 is used as a support, this in turn in the heating chamber at a distance from the heating elements using asbestos blocks 68 and 70 is mounted so that the nested quartz tubes are inclined to ensure that the reactants remain in the hottest area of the oven. According to the other of the two methods (Fig. 14) serves as a carrier for the reactor tube is a fabric tape 138 that is spirally wound around the reactor tube 136, approximately a width 2.5 cm and fills the cylindrical feed opening of the heating chamber of the furnace. This fabric tape can be made from consist of a wide variety of refractory materials, such as asbestos, one in the trade under the name Fiberfrax known fabric or made of a glass fabric. In this case, a glass fabric is preferably used that has an increased Shows security and reliable performance. The importance of using these two different methods is in the explained below.

The starting substances are applied to the system with energy Via the heating element of the stove in the products transferred. If the reactants are exposed to a sufficiently high temperature, while others Zones of the reaction tube at a suitably lower temperature are held, the products from the vapor particles will precipitate or condense. The temperature differential that governs vapor phase transport and synthesis Drives via the vapor phase, is made in a three-zone furnace by a corresponding selection of the different control temperatures applied in the individual heating zones. Each

The heating element of the individual heating zones can be regulated independently of the other elements.

Method 1 (see FIG. 3);

The 50 cm long reactor tube containing the reactants is inside a second quartz tube in the 61 cm long one Heizkairaner of the stove stored. By setting accordingly of the control points of the three heating zones of the furnace can have an at least substantially linearly falling temperature gradient be generated. A temperature gradient Δ T / d can therefore be generated, where T is the temperature and d is the respective one axial distance in the furnace is at least approximately constant between the centers of the two outer heating elements. This linear temperature gradient, which is applied over the longer dimension of the reaction tube, is used the purpose of separating the most diverse product materials formed during the reaction from one another. The Products in a very specific pattern and in a very specific sequence with decreasing deposition temperature: First dark purple to black polycrystalline films, then a ring of massed crystallites; Single crystals or whiskers, red layers with small grain size and polycrystalline morphology; and, in the coldest temperature range of the reactor tube, a dark gray amorphous material.

A series of experiments has shown that this amorphous material does not arise in the sealed reaction tubes when the coldest temperature of the tube is greater than about 375 ⁰ C. Similarly, the occurrence of the red polycrystalline material can be significantly suppressed by keeping the lowest temperature on the reactor tube at or above 450 ° C. Furthermore, the applicant has established that polycrystalline MP ₁₅ cannot be produced in devices which are operated with a single evaporation source. The polycrystalline and amorphous substances formed in this way

-6A-

are all substances with high values of x, for which χ is much larger than 15.

Procedure 2:

The brackets, wound from the woven tape, serve not only to align the reaction tube, but also to align it as effective barriers against heat transfer between the three heating zones. These barriers make you steeper temperature drop between the zones, at the same time however, a flatter gradient within the central zone. The result is a graded Get a temperature profile that can be set and manipulated in such a way that certain target products selectively can be obtained by adjusting the appropriate precipitation temperatures.

A) In von Schnering's announcement of the production of single crystals (whiskers) from KP _ he described the production from the elements in such a way that the heating of the elements, namely potassium and red phosphorus, in a "temperature gradient" of "600/200 ⁰ C" in an approximately 20 cm long quartz tube. He also states that the crystals were formed in the temperature range of "300 to 32O ⁰ C". The ovens used were apparently single heating element ovens in which the temperature gradient is caused by the loss of heat that occurs at one end of the tube protruding from the oven.

As a first step in improving this method, a Three-zone furnace of the type shown in Fig. 3 used in which the heating of the output elements can be monitored and controlled independently of each other

- & * ■ - ■. ■ "

The heating chamber of the πτ-sizonenofen used (Lindberg model 54357) had a length of 61 cm, which made it easier to monitor and regulate the temperature gradient applied. By storing the reaction tube, which now had a length of approximately 52 cm, in a second quars tube, open on both sides, which is supported on asbestos blocks. In this device, a generally linear course of the temperature gradient Δ T / d is set, which is at least approximately constant between the two centers of the two outer sides of the heating elements of the furnace. The electrical power loading of the furnace is monitored with a Lindberg controller (model 59744 / A). With this device three independent controllable regulators are used, which contain independent controllable silicon rectifiers and band regulators, which effect the control of the furnace temperature according to the manual preselection.

The linearly falling gradient, which is maintained and impressed over the long dimensions of the reaction tube, serves to cleanly separate the various products from each other, which are formed in the course of the reaction. These products occur in a characteristic sequence from recurrences with decreasing temperature to dark purple to black polycrystalline films, a ring massed crystallites, single crystals or "whiskers"; fine-grained red films with polycrystalline morphology and, im coldest area of the reaction tube, dark gray amorphous substance.

Example I:

A three-zone furnace (Lindberg, model 54357) as shown in the figure, with heating elements in a refractory material are sunk, in separate cylindrical

BATH ORIGINAL

Sections with lengths of 15.3 cm, 30.6 cm and in turn 15.3 cm (corresponding to 61 cm in total) is required for the implementation used in this example. The diameter of the heating chamber is 8 cm. The temperature is shown in Fig. Thermocouples (not shown) removed, the »measured over the length of 61 cm of the inner furnace tube, arranged are.

The sides of the heating chamber are plugged with glass wool to minimize heat loss from the oven. A quartz tube with a length of 60 cm and a diameter of 4.5 cm is inclined at a small angle and open Asbestos blocks stored arranged in the heating chamber.

The quartz reaction tube has a round bottom in axial section, is 49 cm long and has a diameter of 2.5 cm. The reaction tube then has a section with a narrowed cross section, which is 10 cm long and a Has a diameter of 1.0 cm. Under a dry nitrogen atmosphere 6.51 g of red phosphorus and 0.62 g of potassium are placed in the tube. The atomic ratio of phosphorus to metal is 13.3 to 1. The phosphorus has analytical

-4 purity on. The tube is evacuated to a pressure of 10 mbar and tightly closed by melting the attachment tube. A few centimeters of the extension pipe remain. The total length of the pipe including the attachment is 51.5 cm after melting. The reaction tube closed in this way is placed in the three-zone furnace described above. The temperature in the three heating zones is set to 65O ⁰ C, 45O ⁰ C and 300 ⁰ C, with this temperature distribution for 5 hours heated. The temperature is then reduced for a further 164 hours. The power is then turned off so that the oven can cool to room temperature. This takes place at the cooling rate inherent in the arrangement. The reactor tube is then cut open,

α α β

- 63 "- ■ - ■ _> ■ ■ ■

namely under a dripping nitrogen atmosphere in a Glove box. The products are condensed phases with both crystalline and polycrystalline as well as with amorphous morphology.

Table III shows the various process parameters which were complied with for the various runs are listed “together with the type of product used in each the runs have been received «. Before slicing, the Reaction tubes of the first three runs examined with regard to the location of the separation of the individual products. Observed become a dark ring of massed crystallites, and the beginning of a red polycrystalline film. Become whiskers always observed, between these two points. These positions will later be determined along with certain temperatures assigned to the gradient, which is specified and set by preselecting the temperature in the three heating sons These data are summarized in detail in Table IV.

BATH ORIGINAL

TABLE III

Verse.
. No.

Ρ / Μ
a)

"M

(G)

ρ
(G)

Pressure otter) b)

T ₁ T ~ T ^ ( ⁰ O) ( ⁰ C) ( ⁰ C)

Time
(H)

Pipe length
(cm)

Products

d)

Remarks

• · « 4th • < I. 2 I « * <
C. * <C t
C. * *
t O J I f < 3 I t « I. «C
<C «C
C.
4th ( C. B « 4th <C 5 f
• * # * 4 : * C C

13.3

12.5

15.1

0.21 (K) 6.51 1 χ 10 " ⁴ 650 450 300 164/172 51.5 SC, PC, a Example I

0.67 (K) 6.56 1 χ 1O ^- " ⁵ 600 465 350 138/147 52.0 0.67 (K) 8.02 7 χ 10" ⁴ 550 475 400 236/245 about 52.0

15.0 0.29 (Na) 5.86 9 χ ΙΟ * ⁵ 600 450 375

* ⁵

30.0 0.15 (Na) 6.00 1 χ 10 0.55 (Rb)

-5

600 460 350

72
100.5

S · C. fP.C · Pchr Fehler

a) molar ratio (atom to atom)

b) Pressure during melting in mbar

c) If only one time is given, this is the dwell time at the given gradient. Where two times are given, the second time is the total residence time in the oven.

d) S.C. = Single crystal (or whisker, as often mentioned)

P.C. = polycrystalline material, usually thicker layers (thicker than 10 μΐη) a = amorphous material

* The same trial numbers are used as reference designations throughout all tables OO

TABLE IV

Position of the phosphorus-rich products with large values for χ as a function of the target temperature in the three heating zones of the oven

Vers. Profile
No.

T.

Time
(d)

ring
(cm)

Temp. ( ⁰ C)

Films Temp. Precipitation Zone Temp- (cm) ( ⁰ C) width ^ »*) range ( ⁰ Q

1) 650

2) 600

3) S50

4) βΙΟ

5) SlS

465
475
485

300 1

350 5

400 10

40ö 3

400 3

26 _f 0

26.5

26 _r 0

28 _? 5

30.0

33.0
36.5

34.5
42.0

435
4S0
460
455
450

6.5

13.0

13.5

13.5

40 35 45 55

45

Profiles 1, 2 and 3 were all independently produced on separate samples position added.

Profiles 4 and 5 are reheat profiles recorded for the reaction of the experiment No. 3, which was originally performed with profile 3.

In all samples there is whisker growth in the space between the ring and the Fogging found.

The temperatures set on the display, which are shown in Table IV, have an estimated accuracy of ^ 5 ° C

The indication of the positioning is with an estimated error of approximately + ^ 0.5 cm afflicted.

-α oo cn

CD

The data in the two tables reproduced above were used to establish a relationship between the temperature and the type of product obtained. It then appears that the single crystals of KP _{15 are formed} in the temperature range of approx. 470 j + 10 ⁰ C, with the center shifting slightly from run to run, but within these fluctuations around 465 to 4 75 ⁰ C lies. Similarly, the onset of deposits of red polycrystalline material occurs at approximately 450 ± 10 ^° C. Finally, the amorphous material then precipitates even when the lowest temperature is only about 350 ⁰ C ■. If this temperature is raised to 400 ^° C., no more amorphous material is precipitated (even if this run in which this temperature was used had to be terminated by a collapse of the reaction tube before the products could actually be obtained, this relationship was established between the precipitation temperature and the product for the amorphous material confirmed in later runs with improved methods). The mean value between these two values determined, however, provides a useful limit value for the upper limit of the precipitation of amorphous material at approximately 375 ^° C. The pressure in the heated reaction tubes was not measured.

B) Temperature gradients that favor the growth of single crystals (whiskers):

Using the knowledge from the relationships between the precipitation temperature of the product and the product morphology from the values in Tables III and IV, ways of improving the synthesis technique were sought which had a greater Enable selectivity of the product. Methods have been sought for better setting and handling the temperature profiles in the furnace in such a way that larger areas of the surface of the reactor tube in the corresponding

required temperature range for the precipitation of a specified product. A range of suitable materials with low thermal conductivities and easy to use handling forms were determined with regard to their suitability for creating thermal barriers against heat transfer tested in the oven. Woven asbestos tapes have proven to be a suitable means both for supporting the reaction tube and for creating complex gradients proved particularly suitable. With the help of such asbestos tapes, areas in particular can be pronounced flat, almost isothermal gradient, which is caused by areas with relatively steep gradient jumps against each other are separated ("cross barriers"). Such "stepped" temperature profiles are described in the following Examples are used wherever certain products are to be manufactured with maximum yields.

Another improvement for the more reproducible setting of temperature profiles from one run to the next is that a stronger, ceramic material is used to fill the gaps in the walls of the heating chamber became. During the first runs, these gaps were stuffed with glass wool to counteract the loss of heat could, but was not particularly effective. The large cylindrical gaps that the chamber walls have as the furnace was initially set up to accommodate a reaction tube over its entire length, specifically for experiments with 'flowing medium, and not for closed stationary ones Systems as used for the present experiments and methods.

The following examples are all aimed at promoting the growth of single crystals, both larger sized ones Manufacture single crystals as well as care about these crystals

BATH ORIGINAL

to be obtained in larger yields, both in percentages based on the total forms of the reaction products obtained and in absolute yields. SoI'-chen Response controls and these results have actually been achieved.

Example II:

A furnace of the type also used in Example I (Lindberg, model 54357) with three heating zones is also used in this context Used for example. The control is carried out with the same control device (model 59744-A). The side openings the heating chamber are sealed with refractory ceramic material in order to reduce the heat loss of the furnace. The reaction tube is supported in the heating chamber by two rings made of glued asbestos tape. One of those bands is seen in the longitudinal direction of the heating chamber, at a distance of 1.6 to 19 cm, the other arranged at a distance of 42 to 45 cm. In other words, both carrier rings lie completely within the central hot zone, specifically immediately at their transition to the two outer heating zones. The rings are designed so that the reaction tube is light is held inclined. The rings also serve to isolate the heating zones from one another, as they act as heat transfer barriers works.

The quartz tube used as the reaction tube (FIG. 3) has a rounded bottom, is 48 cm long and has a diameter of 2.5 cm and a narrow connecting pipe 162, the 10 cm is long and 1.0 cm in diameter. 5.47 g of red phosphorus and 0.50 g are obtained under a dry nitrogen atmosphere Potassium entered into the reaction tube. The molar atomic ratio of phosphorus to metal is 15.1. The phosphorus has a purity of 99.9999%. The potassium has a purity of 99.95%. The reaction tube is at a pressure of

-4

10 mbar evacuated and closed by melting the narrowed extension piece of the pipe. As a result, the wide tube is lengthened by a few centimeters, so that the total length of the reaction tube is 52 cm. The melted tube is introduced into the three-zone furnace in the manner described above. The temperature in the three zones is set to 600 ⁰ C, 475 ° C and 450 ⁰ C. The furnace is heated to the setpoint temperature in the course of 4 hours and then operated at this temperature for 76 hours. After this time, all three heating zones are switched off at the same time, so that the oven cools down to ambient temperature with its own characteristics. The tube is cut open under dry nitrogen in a glove box. Crystalline and polycrystalline substances are obtained as products.

Table V summarizes the process parameters for a number of these runs (the data for the above Examples described in detail correspond to experiment No. 10).

P / K
Loading
relationship ( K
G) Table V P.
(G) Pressure ^c)
(mbar) ^T 1
( ⁰ C) T
( ⁰ C) CC) Time ^d)
Target / total Pipe length
(cm) in hours ♦ t
Cp * verse
No. 15.1 0 .58 6.80 9x10 " ⁴ 600 485 450 24/28 50 t ■ «?
1 ι « Ί 6th 4.93 1 .54 6.01 1 χ 10 " ³ 600 485 450 96/106 approx. 48 V & '. 7th 4.98 1 .53 6.03 ? χ 10 " ⁴ 600 475 450 96/106 approx. 49 Y \
C * 8th 15.1 0 .50 ^b 5.98 ^b) 1 χ 10 " ⁴ 600 475 450 144 / 52.5 Ϊ · ■
* <*
t It
t 9 15.1 0 .50 ^b 5.97 ^b) 1 χ 10 " ⁴ 600 475 450 144 / 52.0 10 30.3 0 .25 6:00 am χ 10 " ⁴ 600 470 450 72/78 51.0 11th 29.7
14.3 0
0 .27
.18 (Rb) 6.36
5.70 1 χ 10
1 χ 10 " ⁵ 600
550 470
475 450
400
Approx. 72/78
144 / 51.0
50.0 32478 12th
13th 15th 0 .30 (Na) 6.12 * χ ίο " ⁵ 600 450 375 72 / approx. 50 14th 7th 0 .19 (Li) 5.87 9 χ io ~ ⁵ 600 450 450 72/184 approx. 50 15th Molar atomic ratio
high purity substances: K, 99.95%; P, 99.9999%
Pressure when melting in mbar
Dwell time at a given temperature gradient / total dwell time in the oven a)
b)
c)
d)

Crystalline and polycrystalline substances are obtained in all test runs. The yields of single crystals are always greater than the yields obtained in the process according to Example I. The polycrystalline substances always accumulate as a deposited layer in the colder end of the pipe and are usually limited to the last 10 cm of the pipe length, although the polycrystalline areas sometimes overlap with the single crystal area. The single crystals obtained in these experiments are identified _{as structurally identical to KP 15} by X-ray diffraction diagrams on the powder material. The wet chemical analysis of the crystals turned out to be difficult due to the stability of the crystals. The crystals could hardly be digested for analysis (the analytical data are summarized in Tables VIII to XI).

The polycrystalline fittings were also examined by powder X-ray and wet-chemical methods. The layers showed different degrees of crystallinity, the X-ray diagrams _{resembling the diagrams of KP 1} C in many respects, but differing significantly from these diagrams in numerous features. In addition, the wet analysis in agreement with the flame emission spectroscopy shows that the alkali metal concentration in these substances is only in the ppm range (less than 1000 ppm, often less than 500 ppm), with P / C ratios in the range from * 200 to 1 to 5000 to 1.

C. Thermal gradients that promote the growth of polycrystalline and amorphous substances;

After the successful breakthrough in the production of single crystals, test series were continued with the aim carried out the temperature profile in the three-zone furnace so

vote and to arrange the asbestos rings so as to tune the graded heat gradients so that selectively polycrystalline and amorphous material found in the initial Trial runs obtained can be produced.

The first attempts already provided indications of the temperatures which should be aimed for in order to solve this problem would be. The only question that remained unanswered was the direction in which the optimization should take place. The set temperature profiles and the products obtained with these profiles are shown in Table VI.

Table VI

P / K K P

Vers. Loading

No. Ratio (g) (g)

Pressure '(mbar)

d)

T ₁ T ₂ T ₃

( ⁰ C) ( ⁰ C) ( ⁰ C) time ^e)

Pipe length (cm)

observed products WPa

f)

KZP, _e ^b) 0.50 ^b) 5.63 ^b> 4 χ 10 ~ ⁴ 600 465 350 72Z96

15th

1. 43 5οββ 7th κ 10 1. 49 5 _s 40 9 JC 10 1. 52 β, ΟΟ 1 K 10 1. 25th 4.95 7th K 10

600 425 400 72 / 9β 600 375 350

600 350 350 9§, 5 51.0 50.5

50

IS

225 225 50Z77 37 _a 0

72Z124 47.0

a) molar atomic ratio

b) pure output elements

c) BM: mixture ground in the ball mill

d) Pressure on melting

e) Dwell time at the target temperature gradient / total dwell time in the furnace

f) W: whiskers (single crystal)

P: (polycrystalline layers) a: (amorphous substance) *: product observed

X X

X X

X X

X X

none questionable

questionable

small amount, thin fitting

χ χ · questionable

CJP

P.

OO CD CD

The first test run, which is the subject of Example III below, simply doubles the temperatures of the areas also used in Example I, the linearly falling gradient now becoming a stepped gradient. Unsurprisingly, all types of product are observed in this experiment, but with different amounts compared to the results described in Section A. If the zone of coldest temperature is raised to 400 ^° C., as in the second run of Table VI, no amorphous material is detected as expected. At a temperature of 425 ^° C. in the central section, however, almost 2/3 of the interior of the reaction tube was covered with a polycrystalline coating and only a small number of whiskers were found. In other words, the reaction could be controlled in such a way that almost exclusively polycrystalline coatings were obtained in the reactor tube.

In the third and fourth test run the coldest temperature zone is controlled at 350 ⁰ C, that is cold enough to reduce formation of the amorphous material formed in the first test run and the temperature of the middle zone temperature of 375 ⁰ C to 350 ⁰ C. In these attempts, however, amorphous material was hardly formed in significant amounts. Instead, large amounts of both monocrystalline material and polycrystalline material were found in a rather short section of pipe. Only thin deposits of amorphous material were observed in the remaining pipe sections. The same phenomenon is also observed in the next two test runs, even if at least noticeably thin amorphous layers are formed in one test run. Obviously, most of the steam components condense polycrystalline or monocrystalline in these test runs, namely before significant proportions of the steam up to the

Sections of the reactor tube that are cold enough to reach Formation of the amorphous form are.

Example Ills

The three-zone oven also used in Example 1 is also used for used the experiments of this example. The control also takes place with manual specification of the target temperatures with the rainbow used in the previous experiments. guess. The sides of the heating chamber are covered with a fireproof Material sealed to insulate heat loss from the furnace. The reaction tube is on two asbestos fabric rings stored. One of these rings is based on the length of the Chamber, 16 to 19 cm apart, the other 42 to 45 cm apart. This means that both rings are asbestos lie completely within the central heating zone, directly on the boundaries between the inner ones Heating elements and the heating elements of the two outer heating zones. The asbestos fabrics & attachments are designed in such a way that that the reaction tube is held inclined. The rings serve to hold the reaction tube at the same time the insulation of the heating zones from one another, in that these rings act as heat transfer barriers. ·.

The quartz reactor tube, which is closed on one side, has a rounded one Bottom is 48 cm long and 2.5 cm in diameter and has a 10 cm long and 1.0 cm at the open end wide connection pipe. Under a dry nitrogen atmosphere Put 5.93 g of red phosphorus and 0.50 g of potassium in the tube brought in. The molar atomic ratio of phosphorus to metal is 15. The phosphorus has a purity of 99.9999%. The potassium has a purity of 99.95%. The pipe will open a residual pressure of 4-10 ~ mbar is evacuated Tube closed by melting at this pressure. The extension pipe extends the large part of the pipe by a few Inches so that the pipe including the narrower one

Extension piece has a total length of 51 cm. The pipe melted in this way is placed in the three-zone furnace described above. The temperature in the three heating zones is set to 600 ⁰ C, 465 ° C and 350 ⁰ C. The feed residence time at this temperature profile is 72 hours. The three heating elements of the three heating zones are switched off at the same time after this time and the furnace cools down to the ambient temperature with its own characteristic. The reactor tube is then opened in a glove box under dry nitrogen. As products, single crystals, polycrystalline fittings and amorphous material are obtained.

D. Manufacture of cylindrical pieces of amorphous polyphosphides

The experiments described in Section C show that further improvements to the process must be made in order to produce larger quantities of amorphous material. In order to produce solid amorphous material, not just thin fittings, the production process had to be modified in such a way that the precipitation zone is restricted to narrower areas than in previous attempts. In other words, only the outermost end of the reaction tube should have a temperature of approximately 375 ^° C. or below. In principle, this can be brought about by the heat transfer barriers used in the previous experiments. On the other hand, however, it was to be expected that as long as the conditions for the formation of the other materials, for example monocrystalline MP ₁ , - "crystals or polycrystalline MP -crystals with χ much larger than 15, were present over larger areas of the reactor tube, these would exist under the optimal conditions for them and would act as traps for the transport of steam

Formation of the single crystalline and polycrystalline substances is suppressed. This is achieved in that the Temperatures of the central sections of the reactor tube were raised to a level sufficient for formation of polycrystalline and single crystal material was too high. The only area in which the conditions for The formation of these crystalline substances is now the immediate area of the thermal barrier in which a rapid drop in temperature occurs.

As shown in the following example and summarized in Table VII on the basis of numerous experiments, more were Improvements to the above-described basic structure of the process for producing massive amorphous substances worked up. On the one hand, the heating elements were controlled with the help of a computer (Honeywell, model DCP 7000), whereby the temperature profile and the temperature change could be preprogrammed in such a way that it is reproducible Heat treatments in successive test runs were guaranteed. Through the digital computer control could also be programmed to be heated up and programmed to cool down, causing damage to the reactor tube and the formation of white phosphorus could be avoided. The formation of white phosphorus has often been observed, though the reactor tubes have cooled down too quickly. The phosphorus vapor then condensed in the form of P .. This was also the reason why the substances often seem to be intensified were responsive. By simply extracting the substances in solvents that dissolve white phosphorus, this apparent reaction activity could be canceled again. The second improvement to the process is the measure of impressing an "inverted gradient" with the temperature sequence 3Q0-490-500 ° C over the course of the pipe from the metal / phosphorus source to the precipitation zone the vapor phase transport, creating the precipitation zones

Could be cleaned of material affecting the nucleation process could influence.

The most important improvement, however, relates to the geometry of the reactor tube. Instead of a long pipe with practical With a uniform diameter of 2.5 cm, the pipe body is shortened to a length of 30 to 32 cm and the extension pipe 160 (Fig. 2) extended with the diameter of 10 mm and melted so that this tube over a length of remains about 5 to 7 cm and extends the available interior space of the pipe in this way. If this Section is brought into zone 3 of the three-zone furnace and the furnace with the corresponding vapor transport gradient is acted upon, this narrowed pipe section gradually fills with solid solid cylindrical pieces of substance in increasing length, depending on the improvement of the procedure.

Example V.

The three-zone furnace also used in Example I is operated under numerical temperature control and temperature regulation a computer is used to carry out the heat treatment in a reproducible manner according to a preprogrammed sequence is able to.

The sides of the heating chamber are closed with refractory material, to reduce heat loss from the furnace. The reactor tube is supported by two rings made of asbestos tape. The rings are dimensioned so that the reactor tube is held at a slight incline. The rings also serve the thermal insulation of the heating zones against each other.

The quartz reactor tube is closed on one side with a round bottom, 33 cm long and 2.5 cm in diameter and carries one

tapered pipe socket 162, which is 20 cm long and one Has a diameter of 1.0 cm. Under a dry nitrogen atmosphere 7.92 g of a batch milled and homogenized in a ball mill are given up, in which the molar atomic ratio of phosphorus to metal is 15 to 1

-4 is. The pipe is then to a pressure of 10 mbar

evacuated and sealed by melting. 10 cm of the tapered pipe socket are retained, so that the Total length of the reactor tube is 43 cm. The melted reactor tube is then placed in the three-zone furnace and in this with the fabric tape heat barriers described above held.

In relation to the length of the heating room, the pipe is arranged in the heating room so that it lies between the centimeter marks 6 and 49. One of the thermal barriers is placed between 16 and 19 cm, the other between 38 and 40 cm. The inverted gradient 300, 490, 500 ^° C. is first impressed under computer control 10h. After the furnace with its own characteristic has cooled down, the reactor tube is shifted in the furnace tube so that it lies between the centimeter marks 12 and 55. The thermal barriers are shifted in the range from 18.5 to 21 cm or 44.5 to 47 cm. After the programmed heating Gradiententemperaturen of 600 ⁰ C, 485 ° C and 300 ° C are then adjusted 64 h for the individual temperature zones. The reactor tube is then cooled to a temperature profile with a gradient of 180, 190, 200 ^° C. by programmed cooling. This temperature profile is maintained for 4 hours. The furnace then cools down to ambient temperature with its own characteristics.

The reactor tube is under a dry nitrogen atmosphere cut open. From the tubular extension 160 (Fig. 3) can 4.13 g of each 2 to 3 cm long solid, homogeneous amorphous substance pieces are removed. The results further test runs are summarized in Table VII,

Table VII

Yield of tube length amorphous.,

. . substance

(cm)

K / P ₁₅ BM 6

.1 7 _x ίο " ⁴ 600 440

.-4

.05 ⁸ X ΙΟ "* 600 460

, -5

.72 1 χ 10 600 475

Κ / Ρ ₁₅ ΒΜ

Κ / Ρ ₁₅ ΒΜ

Κ / Ρ ₇ ΒΜ

Κ / Ρ ₁₅ ΒΜ

Κ / Ρ ₅ ΒΜ

Κ / Ρ ₁₅ ΒΜ

Κ / Ρ ₁₅ ΒΜ ¹

5.87 1 χ 10

8.05 7 χ 10

7.39 7 χ 10

7.92 1 χ 10

-5

-4

7.83 7 χ 10
8.0 1 X 10
7.95 1 χ

-4

-5 -4

600

600

600

600

600

600

600

325 300

72/124
64/78

47.0

not confirmed

300/200 64/78

39.0 l.Scnr pieces 38.0 1.5cm pieces

300/200 64.78 40.0 4.0cm pieces

64

64

64

104

104

104

47.0

44.0

43.0

41.0

43.5

45.5

581

36%

52%

12%

53%

54%

OO CD CD

Table VII (continued)

Verse.
No. Batch
{ Weight
9) Pressure*
(mbar) ^T 1
( ⁰ C) ^T 2
( ⁰ C) ^T 3
( ⁰ C) Time
(H) Pipe length
(cm) Yield ar
more amorphous.
Substance ' 30th KZP ₃₅ BM 7.78 7 X 10 " ⁴ 600 500 300 104 35.0 66% 31 KP ₁₂₅ CP 5.40 7 χ 10 " ⁴ 600 500 300 104 34.5 71% 32 KP ₁₅ CP € .96 1 x 10 " ⁵ 600 500 300 104 35.0 51% 33 KbZP ₁₅ BM 7.50 7 χ 10 ~ ⁵ 600 500 300 104 45.5 43.0% 34 RbP ₁₅ CP 7.19 1 X 10 ~ ⁵ 600 500 300 104 33.5 37.1% 35 HaZP ₁₅ BM 8.58 1 x 10 " ⁵ 600 500 300 104 34 46.7% 36 NaP ₁₅ CP 7.45 1 χ ΙΟ " ⁵ 600 500 300 104 34.5 53.7% 37 CsZP ₁₅ BM 9.73 7-x 10 " ⁴ 600 500 300 104 34.0 15.8% 1) Piece length or Weight ^! i, related to I. Jinwaaqe

Solid product as the starting substance

starting batch ground in the ball mill

Pressure when melting

The results show / that the yields are largely independent voxi of the type of substance given up, i.e. regardless of whether the batch was previously in the ball mill has been ground and homogenized, or whether an already pre-reacted solid-state reaction product is used. However, the yield depends strongly on the P / M ratio. The greater the relative metal content in the batch, the lower the product yield. Since the amorphous material consists essentially of phosphorus, it is reflective In this dependence, the reduction in the phosphorus vapor pressure over the metal-phosphorus charge increases with increasing Metal concentration again. This leads directly to a slowdown in the growth rate with otherwise identical thermal conditions.

Table VIII shows some analytical data which were measured on the pieces of amorphous substance are. The potassium concentration in the test items is determined wet-chemically. There are more in the flame emission spectrum Trace impurities can be seen.

Table VIII Trace elements in amorphous MP ^ .- material

Verse no.

Batch

1)

K with AA (ppm)

K / P ₁₅

K / P

15th

K / P

15th

K / P

15th

K / P.

K / P in the emission spectrum ³ . ^} recognizable components with a concentration greater than 1 ppm
(ppm) ^

15th

427 85

20-224 40 285 161

Fe: _β 4-4 Κ: 20-200 Si: 6-60 6-60
less than 30 Al:
Si: 4-40
20-200 Fe:
K: 1-10
not measured As: 2-20 Sit
κ: Accelerated measured Fe: .3-3 Si:
K; 4-40
3-30 As:
K: 20-200
12-120 Si:
N / A: 20-200 K: 20-200 Si:

1) Ball mill only

2) Atomic absorption of the digested sample '. ■■

3) Flame emission spectrographic analysis on non-digested samples

Tables IX, X and XI show the analytical data obtained by wet chemical methods on the vapor phase transport reaction manufactured products were obtained.

Unless expressly stated otherwise, the P / M ratios are which are shown in the tables, always molar atomic ratios.

TABLE IX

SINGLE CRYSTALS (WHISKERS) FROM STEAM PHASE TRANSPORT

Vers. No. Batch P / M total *

38

10 11

17th

K / P ₁₅ 19th 1 94, .5 KZP ₁₅ 19th 1 98 .8th KZP ₁₅ 19th 1 99 .4 KZP ₃₀ 16. 4th 96 .1 KZP ₅ 11. 3 97 .7

* Analytical mass balance% M +% P (found)

Table X AMORPHIC MATERIAL AUG STEAM PHASE TRANSPORT

Verse-

No. Batch P / M total *

39 ^K / P ₁₅ 2500 W.

16 ^K / ^P i5 1750.W

21 K / P ₁₅ 2300 W.

22 ^K / ^p i5 12200 W.

25 K / P _? 3500 W

26 K / P ₁₅ 6200 W.

23 E / P ,.

^X *> 4500 W

24 KZP, e 7000 W 24 ^{K / P} l5 25000 W.

27 Zc

³ > 84000 E

28 KZP ₁ ^ 7800 W

■ ° 82500 E

29 KZF, - 25000 E

100. 3 99 7th 92. 8th 97 * 0 97. , 9 97. ,8th 98 , 2 93
99 .3
.5 99 .7 98 .2 94 .8th

W) wet analysis

E) _ Flame emission spectrum

* 'Analytical mass balance% M +% P (found)

BATH ORIGINAL

39

Jß

10

17th

IS
16

40

Table XI

Analysis of vapor phase transport reaction products

Whiskers

Vers. Batch return no. ■ stood

Ges. P / f5 Ges. P / M Ges.

HT film & ring * P / M

Poly / film
Ges. P / M

Poly / film
Ges. P / M

K / P E / i? K / P K / P K / P

IS

15th

12S

15th

15th

KZPjg $ 2.35 KZP,

KZP KZP

15th

94. S4 19.0S SIi. iC 1170
95.t 10.4

SS.73 IS.10
99.40 July 19

62.36 04/12 95.14 16.35 ISQ. 4 <*> S3. £ & ^

S? .GS 13.1 100.SO 11.3 SS.Sl 213 £ § 71 35G

S3.Sl 35? 93.57 123

SS.Sl 2303 §3.23 54.S

87.Sl 137; 55

30 100.00

i & 0

19th K / i » ₅ 95. OO 2. SO 94.91 13th .3 20th KZP ₁₅ SS. 4th 3. 17th 21 KZP ₁₅ SO. O 3. G7 SG.7 10 .92 22nd
25th KZP ₁₅ 89
91. 2 3.
3. 23
17th 7 & .70 11th .5 26th Concentration camp ₁₅ it. 7th 3. Oil 23 KZP ₁₅ 91. e 2. 60

> 7000

S7 .3 12S0 JS. 97 2300
2300 96 .2 99 95
96 >.
.3
.3 2500
2190
2000 S3. 1 95 .1 4000 95 .40 2200

Amorphous Ges. P / M

1Ö0.3 2S0C

SU. 71 1750 K \ \
N-. O I. 92 .8th 2300 97
97 .0
.5 12200
3500 97 .3 C200 9G .2 4500

Total = sum of the percentages of metal and phosphorus found

Vers. No.

34 27

2E

4 4 «5

Batch residue total P / M

OK 3.23

87.7-3.42

93.3 3.4S

pure

H «/ P ₁₅

H.",/?' _1S

! IsZRbZF ₃₀ Ll '/ p "

KP Whisker Poly / Film Poly / PiIm

Λ *

Ges. P / M Ges. P / M

G «s. P / M 93.3 7003

53.2

9S "S

1250 S3.3 ISSOS

94.13

S8.ee

97.31

> 700

S7.23

> 700

58.71

97.12

57.5 ICQO 97.3 13.10

Ns / ftü 4.3 / 1 Kn / Rb 3.1 / 1

59 1300

36th SS 1200

Amorphous
Ges. P / M

59.5 25000
Si.7

! .2

31.3

> 3 4.030

ÖS.21

95. 17

> 700

7ao

^:> 700

ly ^ o, v; cnn not "'i;> lcrr nKiegoben
'£) M'iU.-Ι 1 L'ji.halt u'jin. Flarriü.Tjiie '!] !! i3i3ic.i! Sspok "., ruS!; c ';. ;; ici in At ^ invorhä 1.!. ti is *) Hachtcrn-.poratur (HT) -rilir-e un.l rings (F: l3. 2)

Remarks

E ii-t> 825ΟΟ

ν V

Well not ^. - +

ri'ichgfrv.'iescn ^, proven ;

CO! ¹ O

OO CD CO

Polyphosphides come in two fundamentally different ways Types of systems have been manufactured, both of which are referred to as "dual source systems" for the purposes of this specification on the manufacturing process with two independent sources, because in both types of plant the metal and the phosphorus are heated separately and independently on either side of the Precipitation zone can be arranged. All experiments described here were carried out in the K-P system.

According to the first method, which is shown schematically in FIG. 11, the phosphorus charge and the potassium charge are arranged at the two opposite ends of a fused glass tube 100. The tube is subjected to a temperature profile of the type shown in Figure 12, this temperature profile being generated in a three-zone furnace. As a result of the profile, the independent and separately arranged charges are brought to an elevated temperature, namely increased relative to the central zone which is arranged between the two zones which contain the starting components. In this middle zone, the constituents of the starting products are _{combined to form the product precipitate KP 1} , - in the form of coatings on the walls of the reactor tube (more complete details are shown in Example V).

The second type of system is shown schematically in FIG. A substantial portion 102 of the reactor tube 134 protrudes from the three-zone furnace 104 and is located on Ambient temperature. This section contains a control valve 106 and a ball joint 108 for leak adjustment certain negative pressures at which the reaction is to be carried out. With this alternative technique of the When the reactor tube is closed, this closing section does not need such high temperatures as during melting

get abandoned. The wide access opening to the pipe allows furthermore the introduction of glass boats that contain the phosphorus or the metal, which is tapered by the Neck of the melted reaction tubes is not possible. The shuttle 112 (Fig. 15) is also constructed in such a way that that on a glass substrate 114 (Fig. 14) applied metals can be brought into the condensation zone on which the product layers can and should be deposited. These film / substrate configurations serve as the Starting point for the construction of components, as will be explained in more detail below.

The section of the reactor tube lying outside the furnace serves as a cold trap for the vapor particles. In particular in the zone of the reactor tube closest to the outlet side arranged phosphorus is deposited in larger quantities in this outer section, namely in the generally in the highly pyrophoric form of white phosphorus. Due to the presence of this cold trap, the vapor pressure conditions lie significantly different in the system of FIG. 14 than in the closed-heating system described above became. From this it is readily understandable that the production of the products in the plant described above The selected temperature conditions cannot be successfully transferred to the system described here. So had to the individually suitable reaction parameters, in particular Temperature parameters for the two-source method described here can be determined again.

Example V:

A quartz tube 100 54 cm long and 2.5 cm in diameter with a 10 cm long and 1.0 cm in diameter Side port 116 (Fig "11) is under with phosphorus and potassium charged with dry nitrogen, the substances being filled in at opposite ends of the tube.

BATH ORIGINAL

The molar atomic ratio of the phosphorus to potassium feed is 15 to 1. The potassium (99.95% pure) becomes initially abandoned in such a way that a small piece of potassium weighing 0.28 g is placed in a collecting beaker 118 is, whose longitudinal axis is directed coaxially to the longitudinal axis of the reactor tube. The ones poured into the cup Pieces of potassium are then melted and solidified again in the cup. The phosphorus (degree of purity 99.9999%) is then introduced in pieces in an amount of 3.33 g into the reactor tube and without difficulty around the beaker 118 around. The reactor tube is then sealed off at the neck 116 under reduced pressure. The pressure when it melts is 7 * 10- mbar.

The reactor tube which has been charged and melted down in this way is then placed in a three-zone furnace of the Lindberg Model 54357-S type in such a way that the three temperature zones are centrally symmetrical to the furnace tube. In contrast to the furnace model No. 54357 used in the previous experiments, which has zone lengths of 15.2, 30.5 and 15.2 cm, the zone lengths in the S model used for this experiment are uniformly 20.3, 20.3 and 20.3 cm. Two asbestos fabric tapes wound spirally on the reactor pipe carry the reactor pipe in the transition areas between heating zones 1 and 2 or 2 and 3. These asbestos tapes not only carry the reactor pipe, but they also isolate the central area from the higher temperatures of the adjacent outer zones. The temperature profile obtained and set in this way is shown schematically in FIG. The three heating zones are acted upon by a computer (Honeywell model DCP-7700) in such a way that, after heating, they ^{generate temperatures of 4 50, 300 and 450 °} C. in the three zones, these gradient temperatures being maintained for 72 hours. Subsequent to this dwell time, the system is systematically controlled and regulated to cool down to room temperature over the course of 15 hours.

The product substances obtained in the reactor tube are analyzed. The reactor tube initially becomes this Zvv_ck cut into 7 equally long sections in a dry nitrogen atmosphere using a Silicon carbide cutting disc. Those in the sections on Coatings found on the pipe walls are removed and examined individually by X-ray. The rest the product yield in each area is subjected to wet chemical analysis.

The P / K ratios of the Nxed beats, which were determined in the individual sections of the reactor tube identified in FIG. 13, are also shown in FIG. For the middle range, in which the temperature T is approximately 300 ^° C., the substance compositions have a ratio of approximately 14 to 1. This analytical value falls within the accuracy of the methods used for the analysis in a range that is to be expected _{for the substance KP 1} <-. The X-ray diffraction diagrams recorded on powder samples were clearer for the substances for which a wet-chemical ratio of P to K of approximately 14 was determined, whereby the X-ray recordings undoubtedly _{matched the spectra of KP ^ 5} , both in the form of the single-crystal whiskers and for the polycrystalline material. In addition, the X-ray diffraction diagrams clearly indicated the presence of both crystalline and amorphous material, in a ratio of approximately 1 to 1. This estimate is based on the observed broadening of the diffraction reflections

Example VI;

The system used in example V is also used. The quartz tube 119 is provided with additional "nozzles" 120 and 122 provided that the two side chambers of the middle chamber

BATH ORIGINAL

(Fig. 16) secrete. Be under dry nitrogen 0.47 g of molten potassium with a purity of 99.95% in the outer shown in Fig. 16 on the right and the chamber of the reactor tube marked with "K", the molten potassium then solidifying there will. The feed tube 124 is then sealed by fusing. Then the on the other side of the chamber, identified by "P" in FIG. 16, phosphorus in an amount of 5.58 g abandoned a purity of 99.9999%. Then the entire reactor tube is evacuated to 10 mbar and through Melting sealed. After the individual nozzle 126 has melted, there is phosphorus in the reactor tube and potassium in a molar atomic ratio of 15 to 1.

The sealed reactor tube 119 has a total length of 41 cm and is arranged in the middle of the three successive 20.3 cm long heating zones of the three-zone furnace (Lindberg, model 54357-S). Two thermal barriers (TB) made of woven asbestos tape, which is wound around the pipe in increasing spirals, hold the pipe at the transitions from Zone 1 to Zone 2 and from Zone 2 to Zone In addition, the middle zone is penetrated by the two outer zones the asbestos mounts are thermally insulated. A computer is used to control the three heating zones of the furnace (Honeywell, model DCP 770). The three zones of the furnace are heated ^{to 50Ov 355 and 700 0 C under computer control.} Here, the phosphorus to 500 ⁰ C, the potassium is heated to 700 ⁰ C. The middle zone is ^{heated to only 300 0} C by the temperature preselection, but due to the incomplete insulation by the fabric tape, heat is transferred from the hot zones on the side to the inner colder zone, so that the actual temperature in this middle precipitation zone is 355 ⁰ C amounts to. This temperature profile is for 80 h

maintain. Then the oven is in the course cooled of 24 h.

The reactor tube 119 is then sawed open under dry nitrogen using a silicon carbide cutting disc. This shows that the nozzle 122 between the potassium zone and the central zone was clogged with a substance which, according to visual inspection, resembled _{a multi-fiber KP ^ 5.} In the central zone, thin red fittings, a thicker dark red fitting, and a number of relatively large pieces of monolithic substance were found. The two largest pieces each had a length of around 4 cm, a width of 1 cm and a maximum thickness of around 4 mm. One side of each of these pieces was relatively flat, while the opposite side was convex, since this side grew on the round walls of the reaction tube.

Wet analysis of this material showed that the substance was extremely low in potassium after an analysis of the substance less than 60 ppm. Electron spectroscopic examination and analysis (ESCAi shows that the potassium content of this substance with increasing distance from the reactor tube walls on which the precipitate initially began to form, rapidly decreasing. At a distance of 10 nm the ratio P / K is already approximately 5Oo The ESCA measurements of the P-C ratio on the final surface of the deposited material shows a value on the order of 1000. The radiographic Studies show that the substance is amorphous.

Example VII;

0.19 g of molten potassium are added under dry nitrogen (99.95% pure) placed in one of the outer sections 128 (5 cm long) of a Pyrex boat 112 (Fig. 15). The metal is made to freeze there. Two flat glass substrates 114 (see FIG. 14), each approximately 7.5 cm in length and 1 cm Widths are placed side by side in the shuttle so that they fill the 15.3 cm long central section 130. then 1.36 g of Phorphor (99.9999% pure; obtained from Johnson Matthey) on opposite page 132 of the Schiffchens registered. The phosphorus is granular with a mixed grain size. The granular phosphorus is flowable and readily fills the bottom of portion 132 of the shuttle. The ones also made of Pyrex glass Cross dividers 113 prevent the phosphorus and potassium as well as the substrates in the boat 112 from sliding into one another. The boat 112, which is 35 cm long in total, is then cautious pushed into a serving as a reactor chamber 134 Pyrex tube, which is 60 cm long and 2.5 cm in diameter (Fig. 14). The boat is pushed into the reactor tube until section 128 of the boat, the. is filled with the potassium, abuts the round bottom 136 of the Pyrex tube 134, which is closed on one side. One made from butadyenenitrile rubber Existing O-ring of size 124 is then inserted into the O-ring coupling 102. The Teflon control valve 106 (ChemVac, Ine) is then sealed tightly. To The control valve is then connected to a vacuum line 106 is opened again and the chamber is pumped out to a pressure of 10 mbar. After reaching this pressure, it will The valve is closed again and the reactor chamber is hermetically sealed closed.

The reactor chamber is in a three-zone furnace (Lindberg, model 54357-S). In the manner shown in Fig. 14 are

two ribbons 137 and 139- ". us glass fiber cloth spirally around the Tube wound around and carry the reactor tube at the transitions from zone 1 to zone 2 and from zone 2 to Zone 3 «These tape wraps form heating cabinets (TB) and are arranged so that they are just completely inside the in the middle of the furnace. A third spiral wound tape roll 138 serves as a support and thermal insulation at the point where the reactor tube emerges from the heating chamber of the furnace. A cylindrical plug 140 made of a ceramic-like material serves to reduce of heat losses from the opposite furnace opening.

The arrangement is dimensioned such that the section 128 of the boat 112, which contains the potassium, lies in the region of the third furnace zone, while the section 130, which contains the Contains substrates, is located in the middle area, i.e. in the second heating zone of the furnace, and the section 132 of the boat, containing the phosphorus is in the first heating zone of the furnace. In addition, a relatively large section protrudes the reactor system out of the furnace and is located on Room temperature.

The three heating zones of the oven are computer controlled (Honeywell, model DCT 7700). During a warm-up period, the temperature is brought in the three heating zones 100, 150 and 100 ⁰ C in the phosphor zone, the substrate zone and the potassium zone. The temperature is then as quickly as possible, namely approximately in 18 minutes, to the target temperature profile of 500, 300, 400 ^° C. The set temperature profile is maintained for approximately 8 hours. The furnace then cools down with its own characteristic until the temperature profile 100, 100, 100 ^° C. is reached after approximately 10 hours. The oven is then allowed to cool further to room temperature.

BATH ORIGINAL

- / ZO -

After reaching room temperature, the reactor tube 134 is removed from the furnace. The one lying outside the furnace Pipe section contains deposits of white, yellow and yellow-red substances, which are very likely to be is phosphorus in various degrees of polymerization. The heating zone that originally used the phosphorus contained was free of substance at this point in time. On the other hand, the potassium zone contained the most varied substances, their Colors varied from dark brown to yellow to orange.

The substances of the potassium zone also extended slightly into the area of the central zone, the rest of them half of its length, adjacent to the potassium zone, was covered with a dark coating that was permeable to red light is when a corresponding light source has been viewed through. The remainder of the central zone of the The shuttle was devoid of substance. The reactor tube is opened under dry nitrogen, the boat 112 pulled out and the substrates covered with the red coating taken out of the boat and used for later analysis placed in a tightly closed vessel. If that's in the reactor tube Any remaining material exposed to the surrounding air will burn off the phosphorus deposits in the released areas of the pipe relatively violently, even if those areas closest to the source of phosphorus were not so strong Showed responsiveness. Those in the potassium zone or im Substances remaining in the area of the potassium source reacted violently when exposed to the influence of moisture became. Mostly they burned down violently, which is obviously due to the formation of hydrogen by water reduction is.

The experiment described above is carried out repeatedly. The data of the examples are compiled in detail in Table XII.

TABLE XII

Verse.

Temperatures

Time

Substrate

Low oven

ied

4β 47

4i

50 51 52 53

54

SOO 300 500 300

4?

550 525 52S

306

300

300

300

300

500 300

0 ΛΒ 1 φ 47 Glass Θ .19 1ο43 Glass and Ni on glass Q ο € 2 1 ₀ §2 Wi on glass θ .27 I _n S2 Glass 0 .15 1.66 Glass 0 ' .20 1ο72 Glass 0 ο 21 1ο54 Glass 0 .21 1 * 56 Ni / Au / N

1.0 3.0

6.5 7.0

1.51 Ni / Au / Ni

1000Α ^β / 700Α ^β / 1000Α ^β

B B B

For the production of the dark, red-light-permeable layers, boundary conditions are set. If the temperatures in the two source zones are lowered slightly, for example in experiment No. 49 in Table XII, the amount of product material formed decreases drastically, which is expressed in a shortening of the length of the covering or the precipitation in the central zone. In the same way, the subtle differences in the performance characteristics of the two otherwise identical models of the three-zone ovens that are used for these tests must be taken into account. For example, the temperature of the phosphorus source in the second furnace (B) had to be kept higher (see experiments Nos. 50, 51 and 52). Increasing the temperature of the phosphorus source to 5 50 ⁰ C leads to good results, while an increase to only 225 ⁰ C leads to significantly better results.

The analysis of the substances obtained in experiments nos. 46, 47 and 48 is carried out with a scanning electron microscope using electron diffraction analysis (SEM-EDAX). The analysis showed that the layers are KP ₁ [- layers with a thickness of the order of 6 to 7 μm. The layers are amorphous, without any structural elements being discernible in the scanning electronic micrographs.

Summary of the parameters for the vapor phase transport reaction

The process features and process parameters for control the type of products are the following:

(1) Use a three-zone oven for more uniform temperature control;

(2) greater lengths of reactor tube;

(3) The use of "! Irra barriers for improved Design of temperature gradients;

(4) Use of hot plugs on the ends of the stove pipe ; and

(5) Use of pipe extension sections with a narrower cross-section to produce cylindrical pieces of substance.

For the single source steam policy transport method, the observe the following process parameters:

(1) reaction zone temperatures in the range from 650 to 550 ⁰ C; the cold precipitation zone should have temperatures in the range from 450 to 300 ⁰ C;

(2) The precipitation _{temperature for KP 1} , - single crystals lies in a range of _ + 25 ⁰ C around a central value of 465 to 475 ° C.

(3) The deposition temperature for polycrystalline layers is in the range of 455 ⁰ C down to 375 ° C;

(5) The WiederSchlagstmperatür for the amorphous forms of the new forms of phosphorus are in the range of about 375 ° C down to at least 300 ⁰ C (even lower temperatures, the Applicant has not yet been checked). '

The framework for the process parameters for the two-source vapor phase transport process for the production of massive KP-c ~ substance pieces in a device according to FIG. 11 can be given as follows: phosphorus source ^{temperature at 450 °} C., potassium source temperature ^{at 450 ° C.} Precipitation zone at 300 ⁰ C. The precipitations are relatively thick layers

BATH ORIGINAL

from mixtures of polycrystalline and amorphous KP ₁₁ - for the production of lumpy amorphous KP (x much larger than 15; a new form of phosphor; device according to Fig. 16) phosphorus at 500 ⁰ C, potassium at 700 ⁰ C and precipitation zone at 355 ⁰ C. the potassium source is prone to clogging, and the precipitate is amorphous solid KP. For thin amorphous KP .. ^ layers (device according to FIG. 14) phosphorus at 500 ^° C., potassium at 400 ^° C. and substrate at 300 ^° C.

For thin layers of KP ₁ C, the temperature of the phosphorus ^{source can be raised up to 525 0} C, whereby amorphous KP ₁ ^ is still formed. If the temperature of the phosphorus source falls below 475 ° C, the system will no _{longer receive KP 1} , -. If the temperature of the potassium source falls below 375 ° C, KP _{15 is} no longer obtained in the system either. The substrate ^{temperature can be raised to 315 °} C., good yields of KP ₁ r still being obtained at this temperature. KP ₁ , - is no longer obtained if the substrate temperature is raised above 325 ° C.

Production of polycrystalline metal phosphides in large quantities Quantities according to the solid-state reaction method

Even if the alkali metal polyphosphides of the MP ₅ , MP _ and MP ₁₁ types cannot be produced in a physical state which enables the semiconductor properties which are in a favorable range to be used directly, these substances can, however, be obtained in gram quantities and in larger quantities by the than Solid-state reaction known methods are produced. Before carrying out the process, the reaction components are mixed thoroughly with one another in a ball mill. Quantities on the order of 10 grams or more

of the elements are put in the required molar atomic ratio of phosphorus to metaxi, for example P / M 15 to 1 for MP-.gr under nitrogen in a ball mill. After the fixed closing of the ball mill is ground at least 14h to mince the discontinued output elements to homogenize and in a free-flowing powder to convert "Here v / ground the ball mill during milling is preferably about 20 heated to about 100 ⁰ C h. This measure can improve the flowability of the metal component during grinding.

A portion of the ground mixture, generally at least 10 g, is transferred to a quartz ampoule and sealed under dry nitrogen =, the quartz ampoule usually has a diameter of about 2.5 cm and a length in the range from 6.5 to 25 cm, each according to the size of the feed to be processed. The ampoule is under reduced pressure, in general
closed.

—4 generally at pressures of less than TO mbar, verDie The reaction is carried out in such a way that the sealed ampoule is heated under isothermal conditions until a temperature in the range of 500 to 525 ° C is reached ο Under "isothermal conditions" is im The context of the description means that the entire mass of the material, as far as this is possible and practicable, always has the same temperature to suppress vapor transport from hot to cold areas in the feed, which would give rise to the formation of non-homogeneous reaction products, The highest temperature at which the feed is tempered, is maintained for a longer time, during this residence time at the tempering temperature forms the powdery polycrystalline or the coarsely crystalline product. The residence time during annealing is in Rule 72 h. The longer the reaction at the annealing temperature

BAD ORlGINAL

is carried out, the more crystalline the product becomes, which results in an increase in grain size, a The X-ray diffraction reflexes become sharper and are expressed in other corresponding characteristic data. Cooling off the hot Reaction tube or ampoule to room temperature usually takes place over a longer cooling period, which is preferably in the range of greater than 10h. The slow cooling is not important for the reaction, but prevents the quartz ampoule from cracking due to the different coefficients of thermal expansion of the product formed and the material of the Ampoule, namely of quartz.

Both the heating period and the cooling period should be relatively long, preferably at least 10h, be designed with a tempering at intermediate temperatures of for example 200, 300, 400, 450 ⁰ C for 4 to 6 hours as far as possible. If these rules are not followed, the sealed ampoules tend to explode. The products of the solid state reactions, however, are the same as with the slow cooling except that the small amounts of residual phosphorus are white instead of red.

Example VIII;

19.5 g of a ball milled mixture of Analytically pure phosphorus and potassium in a molar atomic ratio of 15 to 1 are placed in a quartz ampoule with given a length of 6.5 cm and a diameter of 2.5 cm. The ampoule runs out into an 8 cm long neck, which has a diameter of 1.0 cm. The charging takes place in a dry nitrogen atmosphere. The ampoule

-4 is then melted off under reduced pressure (10 mbar), leaving about 1 cm of the narrowed area.

The closed tubular pipe is held in the middle zone of a three-zone furnace (Lindberg, model 54357) in a second quartz tube or a lining, which in turn is mounted on asbestos blocks on the central axis of the furnace tube. The heating elements of the three-zone oven are controlled by a computer (Honeywell, model DCP 7700), by means of which a preprogrammed heating program can be controlled in a reproducible manner. The reaction tube or the ampoule are reproducibly subjected to the following temperature profile? 100 ^° C, 1h; 450 ° C, 6h; 500 ^° C., 18h; 525 ° C, 72h; 300 ^° C., 2h and 200 ^° C., 4h. If all three zones of the furnace are set to the same temperature, the central zone of the furnace is extremely well isothermal, with a temperature variance of less than 1 ⁰ C over the entire zone »

After the furnace has cooled down again to ambient temperature with its own characteristics, the ampoule is removed from the furnace and opened with a silicon carbide saw under dry nitrogen. A dark purple polycrystalline mass is removed from the ampoule. Wet analysis of the product shows a P / K ratio of approximately 14.2 to 1, which value corresponds to the theoretical value of 15 to 1 within an accuracy of approximately 6%. As shown in Table XIII, the other tests with K / P also fall. ₅ batches well in this value range.

TABLE XIII Solid products

Vers. Charge. relationship product ) not determined Ges - feed Highest Zext bex
Maximum,.,
Temp. (Η) Total
lingering Ax pressure t ι k <4 · I No. KYP ₁₅ ** When closing i ^ aukt (G) TO 120.5 Oil 7x (mbar) (f t 55 k / p " IS.3 • 5.5 5.5 500 305.0 140 Ix I. 56 15.5 99.0 21.2 525 266.0 320 Ix ¹⁰ O 57 K / Pi: (pure) 16.2 97.2 9.2 525 216.0 380 ¹⁰ -4 58 k / p " 14.0 99.3 1.· 525 72.0 292 TX ¹⁰ y 59 k / p " 14.2 94.0 19.2 525 72.0 120 P ^{x 10} -4 * 60 k / p " 13.6 96.5 17.7 525 72.0 120 ? x ¹⁰ -4 61 Rb / P ?. 14.7 97.1 16.7 525 216.0 120 N.D "Ιί t 4 62 Rb / P " 14.9 99.8 9.4 525 72.0 292 ? x 10 * 't *. 63 Ct / Pf «(pure) 12.9 97.05 16.1 525 120.0 120 "i X • "j 64 Ci / Pi '(pure «) 15.5 95.S. 13.9 500 260.0 390 7 x ¹⁰ Is 65 Ν · / Ρ ,? N.D. N.D. 15.9 500 216.0 710 ix 10 \ 66 N * / P, e (Pure) 19.2 97.7 9.1 525 260.0 292 4 χ ¹⁰ Is 67 Li / P ,? 14.9 92.7 13.5 500 144.0 710 Λ χ ίο! 68 Rb / rfTPuro) 16.35 96.9 7.8 525 72.0 240 1 χ ¹⁰ I? 69 Rb / P, (Purc) 6.2 96.8 16.3 500 72.0 130 Λ χ "4 70 Cs / p '(Pure) N.O. N.D. 17.2 500 72.0 130 Λ χ 71 Cs / p '(Pure) 7.1 96.2 18.6 500 172.0 130 Λ χ ^1Ο -4 72 Na / P, N.D. N.D. 7.9 500 168.0 290 ? χ ιοί; 73 K / P, I 6.5 93.6 11.5 SOO 72.0 360 4 X ¹⁰ 4 CO 74 K / P "(pure) N.D. N.O. 14.7 525 144.0 120 Ψ X ¹⁰ -3 75 .. k / p " N. D. N.O. 16.1 525 169.0 240 ?. χ ¹⁰ years £ ί 76 k / p " N.D. N.O. 31.9 500 144.0 330 Λ χ OO
Μι 77 k / p " N.D. N.D. 28.4 525 144.0 240 1 χ · ίο :; CJ)
CD . 78 K / P ¹⁵ N.O. N.D. 36.4 525 72.0 240 ¹⁰ Is 79 * Example N. D. N.D. 32.1 525 124 10 ⁵ N.D

In addition, different samples from different Test runs morphologically analyzed. X-ray diffraction diagrams of powder samples can easily be reconciled with X-ray diffraction diagrams for these test specimens derived from KP -, - single crystals produced by vapor phase transport reaction have been produced according to processes cited elsewhere.

Methodologically, the investigation was also carried out on other metal-phosphorus systems as indicated in the tables. A comparison of the X-ray diffraction data of all of these Show substances with one another and with comparative diagrams made from single crystal material overall the mutually analogous nature of the products, i.e. that all these substances at least essentially consist of the same pentagonals aligned parallel to one another Columns consist of covalently bound phosphorus.

Grinding the metals with red phosphorus

For the production of homojener mixtures and for the production of a intimate contact between the red phosphorus and the metals of the first and fifth main group of the periodic table of the elements, ball mills are used.

The milled products are relatively stable in the air and provide ■ starting materials that can be conveniently handled and can be used both for the solid-state reactions and for the single-source processes of vapor phase transport technology can. The stability of this ground Geraische indicates that already during grinding at least partially Have formed polyphosphides.

BATH ORIGINAL

- / 3o -

The metals of the first main group of the priodic system (group 1a) with the exception of lithium are in the ball mill easy to grind with red phosphorus. In particular with the lower melting metals such as Rubidium and Cesium have the option and the process of grinding the starting components in the ball mill, proven. Problems only arise when the ratio for the alkali metals M / P is from 1/15 to 1/7 is changed. Due to the increased metal content, agglomeration of the grist generally occurs on the Walls of the ball mill. However, the material caked onto the walls of the ball mill can be scraped off relatively easily and press it through a sieve, for example a sieve with a mesh size of 1.7 mm, and crush it. Only lithium and arsenic are a little more difficult to grind, at least in conventional ball mills, because both substances have higher melting points and are harder.

While the experiments were initially carried out with pure metals and pure phosphorus, now and in of the following description only high-purity metals and red phosphorus with electronic quality are used (Johnson Matthey; Degrees of purity of 99.999% and 99.9999%).

The usual ball milling with a drive of the ball mill on a rotary table has initially proven to be the best method of mixing the components in the M / P system proven. In particular, the elements of the 5th main group of the periodic table had become more intensive Grinding methods, in particular cryogenic grinding and grinding in vibratory mills, proved to be more suitable.

The ball mills made of stainless steel with the configuration shown in FIG. 1 are manufactured by the applicant.

The ball mill is a cylindrical vessel with an outside diameter of 11.4 era, a height of 15.2 cm and a wall thickness of 0.64 now, the collar of the cylindrical vessel has an inner flange 151 on which a Viton O-ring 152 rests «A lid 154 made of stainless steel is opened by a bolt 155 in which a clamping screw 156 is guided pressed the sealing ring and the flange.

A ball mill has smooth inner walls. The second ball mill is equipped with three baffles, which are on the inner walls the ball mill are welded and extend from the collar to the bottom of the vessel. These baffles act as Lifters for the balls and for the grist, which intensifies the grinding process.

The ball mills described above can be charged with 50 to 60 g of reagent mixture. While for the first Trials balls with a diameter of 0.64 mm were used ρ has been shown in the course of the work that with a mixture of balls with a diameter of 0.64 mm on the one hand and a diameter of 0.32 mm on the other better results can be achieved. All balls are made of stainless steel »

Cryogenic milling is done at -196 ° C in a Spex freezer mill carried out.

The mill used by the applicant was for feeds in the order of 2 to 3 g. Liquid nitrogen is used as the coolant. To achieve good grinding results only relatively short grinding sides were required with the low loading masses, namely meals in the In the order of a few minutes. Cryogenic milling is used in particular to pulverize harder and higher melting metals, especially in the present case

BATH ORIGINAL

for lithium and arsenic. These elements can then be mixed with red phosphorus in a rotary ball mill or ± H be ground in a vibrating mill.

A commercially available mill under the name Vibratom is used as a vibrating mill. It is about This mill is basically a ball mill / but instead of the rotary drive running in one plane is driven in circular oscillations, which are similar to a common shaker. The vibrating mills have an outside diameter of 13.3 cm, a height of 8.9 cm and a wall thickness of 0.3 cm. The vibrating mill has no baffle inside. the Vibrating mill is used for difficult grist, in the context of the present experiments in particular for arsenic.

The grinding time required in each case is subject to wide variations. In general, with hot grinding with at least 40 hours and rarely more than 100 hours can be expected. Besides other factors, this also depends on the load away. Less time is required for grinding the lower melting alkali metals, especially than for systems which contain cesium or rubidium.

Grinding is carried out depending on the type of the feed either at room temperature or under external heating at temperatures of about 100 ⁰ C. The heating is effected using Heiζlampen. The grinding at ambient temperature is particularly suitable for systems with metals having a low melting point, thus in particular for cesium (28.7 ⁰ C) and rubidium (38.9 ⁰ C). A heating by the external heat lamp to temperatures in the range 7 5 to 100 ⁰ C for 3 to 4 h showed very good effect in the case of sodium (97.8 ⁰ C) and potassium (63.7 ⁰ C) and systems that these contained metals. Heating to 100 ⁰ C showed little effect when grinding lithium, the one

Has melting point of 108.5 ^U C. The grinding tests show that when molten alkali metals are ground with phosphorus as the grinding product, relatively stable chemical reaction products are obtained.

Example IX (Experiment No. 88 “ Table xiv).

A ball mill made of stainless steel without conductive foil, which has 884 g of stainless steel balls with a diameter of 0.64 cm, is placed under nitrogen in a dry box, with 6.14 g (0.147 mol) of 99 “95% pure potassium (United Mineral and Chem. . Co ») and 72.95 g (2.36 mol) of 99.9999 % pure red phosphorus (Johnson Matthey Chem.). The mill is closed and rotationally accelerated on a roller table for 71 hours. The ball mill is heated by indirect heating of the outer surface of the pulverizing casing with a heat lamp for 4 hours at about 100 ⁰ C. After the grinding operation is complete, the ground material is placed in a dry box on a sieve with a mesh size of 107 mm and a collecting vessel placed underneath. The product showed no agglomeration. The steel balls are separated from the grist on the sieve. A total of 76.4 g of black, finely powdered grist is obtained.

Example X {attempt Mr. 115, table xiv)

Under nitrogen in a dry box, a stainless steel ball mill provided with baffles is filled with 450 g stainless steel balls with a diameter of 0.64 cm and 450 g stainless steel balls with a diameter of 0.32 cm with 12.2 g (0.0912 mol) 99.98 % pure cesium (Alfa / Ventron Corp.) and 19.77 g CO, 638 mol) 99.99% pure red phosphorus (Johnson Matthey Chem.). The mill is closed and rotated on a roller table for 46.5 hours at room

BATH ORIGINAL

temperature driven. The ball mill is not heated externally. When opening the ball mill in a drying room a practically complete agglomeration of the grist is observed on the walls of the mill body. The grist is scraped off with a spatula and discharged and transferred to a sieve with a mesh size of 1.7 mm given. The chunks of product are then crushed on the sieve. A total of 27.8 g of product are placed in the collecting vessel collected.

Table XIV shows the results of the various grinding tests for the various metals with red Phosphorus compiled. As already mentioned, show the ground products, i.e. that from the ball mill removed grist, a surprising chemical resistance.

Table XIV

Milling the metal with red phosphorus

Vers. Grinding feed weight and delivery

No. comp. Ratio reagent unit source

travel

Grinding temperature result duration

(H)

Qi oh (o, ₀ ) K / P Oi K / l? 02 SHSosgS K / P 03 IS / 5?

OS

it

S3

fl

BM

U / 9

1§

R / P

IS

K / P.

K / P

11th

QofeO !?

80I3O !? OoEjoj?

»Reagens fraie J, T ₀ Sagos'

United Mia <, - Oaeo

31.89 p-s

20f K-seagsafe frade J «T. P- = raagent grade J.Τ »

just right

P.14g K =
72.

S, 14f K-72.95f 9

Sf K-reagent grade JT Ba & er SS = Ig P-reagent grade 3. T. Baker

f K-99.95%

42.61f P-sfeeut

«Nifeeä Min-Ctem 79..6 Atomic slings

(1) powder, - no agglomeration

(2) powder; low agglomeration ■

(3) powder, pressed through 1.7mm sieve; strong agglomeration

98 ° e? 66

12.6 g (1)

22.7 g (2) 19.7 g (1)

52.4 g (2) 49.9 g (1)

28.6 g (I), - P *

unmilled

52.6 g (1) ^O «» '«5.S hrs) 54.0 g (1)

tasi 76.4 g powder

'100 ^e C (3rd hrs) 154.8 g PuIv * -

(0.43g K un.a; -.len)

2eO "eC« hral 63 g (1) IQO ⁵ CiI hr) ⁴⁴ ' ^{6 g (1)}

92

13 94 9S 9t 97 91

Table XIV (continued) Milling the Metal with Red Phosphorus

Proceed with vers. Meal no

Loading ratio

Weighed-in weight and reagent unit

Source of supply

Grinding time

Temperature result

BM (Cd)

BM (b, d) BM (b.e)

BM (b, d)

BM (b, e) X / P _s BM (ae)

x-reagent «rade J.T. Baker

27.72g »-reagent grade J.T. Baker

7g x-r * ag "nt" rade J.T. Baker

31. Ig »-reagent grade J.T. Baker

10g X-reagent grade J.T. Baker 55.45g »-about 99.95%

S. «9 K-99.95« 21.729 »-99.999%

I 9 agent

31. (19 ^ -approx

99.95% Chewtals

Alfa / Ventron Johnson Matthey

JT Baker
Atoms? ic
Chencitala

19.0

41.5

41.0

52.0

BM + CM + VM »/As./». Cb.eHa.e) * ^l

(1> powder? No agglomeration

(2) powder; low agglomeration

(3) powder; pressed through 1.7 mm sieve; strong agglomeration

2.59 K-reagent grade J.T. Dacians (6.5 9.51g As-99.9% Alfa / Ventron 25.74g »-reagent grade J.T. Baker

3.3S «? X-99.95% Alfa / Ventron 1) 215 BM 25.6Ig As lu »p-99.9999 Johnson Matthey 2) 94 VK 29.19g »-99.9991 Johnson Matthey 3) separated

out As t cryo- • Ji lied Upex Mill) (CM)

4) reconbine s ball mill 50 hr «

1SO * C (3 hr »)

100 * C (3 hr) 100 * C (4 hrs)

100 »C (3 hr ·) 100» C <3 hrs) 101 * C (Cfi. 5 hrs)

30.2 g (3)

43.7 q agglomerate?

62.6 g (3)

29.7 ς (3) 36.2 ς O)

36.0 g (1)

100 * C (2.5 hrs)

ambient AS not grindable 4. 2 «in.cycles AS not grindable

at-19 "" C

AS crushed

Room temp.

not agglom.

Table XIV (continued)
Grinding the metal with red phosphorus

verse. Meal- Wr, ¥ he travel

Charge “Weighed in weight and Liefor-Verb reagent unit source

Meal-

duration

(H)

Temperature result

99

DKl

f 33 Ҥ3g Ao

§2 β 2Sg

S ₀ SOg SS ₀ OQg Sfe

3 *% ο

Ώα / 9

IS

ic 92g

3IUIf

P.99§

Offe! Ma / Po 6.2t

S§, J

IiS

$ 3.569 P ^ ffeafent fraie 3 » I.69

4t.Iff

ff.ISf

(Ϊ) powder? no agglomeration

(2) Pulper 1 small agglOBe ^ e ^ ioa

(3) Palmer, through 1 _? ? βι sieve godrüekt; strength

QOoS 2.33 οΘ

SäsoS

67 «

S3 feel)

oppseeso <3 (S «,« f (3)

f 12> s e'.was

fesei

Äauratemp "

19.6 g (1)

39.3 g (1)
91.5 g (1)

63.9 g (1)

52.5 g powder

(0.17g Li unmilled) ^ O

50.36 g powder _ ^

(0.44 g Li unmilled)> ^ j

.00

CD

CD

Table XIV (continued)
Grinding the metal with red phosphorus

Vers. Grinding feed weight and delivery No. comp. Reagent unit source

travel

Grinding temperature duration

101 109 110

111

112 113

114 115

• HU. ·)
■ Mt ·, ·) • Mb, ·)

BM

BMfb.d) BN (b, d)

BM (b, d) BM (b.d)

S.SCg Bb-99.93% JULfaTVentron CS.0 aabient

30 * 22 "P-reagent grade J.T. Baker

5.74g Rb-99.93% Alia / Ventron 115.5 aeblent

31.2g P-99.999% Johnton Matthey

11.22 «Bb-99.93% Alfa / Ventron 41.0 ambient

21.4Sg P-99.999% Johnton Matthey

CiZP

CeZP ₇ CfZP ₇

14.479 Ce> 99.9t% 50.519 P-99.9999%

P.129 Ce-99.91% 20.34 «P-99.999%

12.309 Ce-99.91% 20.069 P-99.999 *

12.3C9 Ct-99.9% 20.1 * 9 P-99.999%

12,129 Cf-99.9% 19.77g P-99.999% Alf «A« ntro Johnton Matthcy

47.5 aebient

AlfaZVeatron C7.0 Johnton Matthey

Alf «ZV« ntron 41.0 Johnfon Matthey

AlfeZVantron 11.5 Johnton tutthcy

AlfaAentron 4 «. S. Johnton Matthey

eadbient

eabient

(1) powder; no agglomeration

(2) powder; low agglomeration

(3) powder, forced through 1.7mm sieve; strong agglomeration

Result

(1)

35.7 g (1)

36.2 g (3); Aggl. almost completely.

€ D, 2 g (3);

23.76 g (1) 29.1 g (3)

26.5 g (3)

27.8 g (3); almost 100% aggl.

In Table XV, the various substances of the formula MP (X = 15 and χ are much larger than 15, corresponding to a new phosphorus form),. which have been produced by the vapor phase transport reaction with one source (1S-VT) , the vapor phase transport reaction with two sources (2S-VT) , by solid-state reaction and by chemical reaction and vapor deposition (CFDl).

Table XV

SS Il σ V & 1

Single crystals X

poiykrist. - _{Θ ff}

amorphous m

Single crystals

2§- ¥ for _ir

polylcrist.
amorphous

Sinking crystals j?

body-, ^ ₁

reaction polycryst. @

amorphous

Xs = crystals / whiskers

B: = pieces, stronger than TO \ m

TF; = Thin layers, less than 10 in thick Β ^Λ ; = Puiver

BATH ORIGINAL

The products obtained by the methods described above are crystals or whiskers (in Table XV as "X" denoted), solid polycrystalline material (denoted "B" in Table XV), solid thin films or Fittings (referred to as "TF" in Table XV), solid amorphous material ("B" and "TF") and powder material in larger amount as obtained on the solid state reaction ("B *").

The analysis of the crystalline MP ₁₅ substances has already been explained in connection with the description of FIGS. As indicated in Table XV, polycrystalline and amorphous MP _{15 has} only been produced in the form of thin layers and fittings.

Polycrystalline material in substance and thin layers of KP (x much larger than 15) are produced by vapor phase

transport reaction with evaporation from a source or. obtained from two sources. These polycrystalline thin films with nucleation on a glass substrate or on the glass walls of the reactor have a dense packing of small whiskers aligned parallel to one another, which "grow perpendicular to the substrate". Scanning electron microscope micrographs as shown in FIGS. 18, 19 and 20 show relatively large gaps between the individual KP whiskers.

These polycrystalline thin layers are formed at these temperatures in the range from 455 ^° C. to 375 ^° C., that is to say up to the limit at which the amorphous phases begin to form.

These substances are examined using wet chemistry, X-ray technology and the electron diffraction spectrum. The results show consistently that the parameter χ in these substances is much greater than 15, typically than

- VfT-

1 000. A typical X-ray diffraction diagram that an powder crystalline material from MP with χ much larger was recorded as 15, is shown in Fig. 10 "

As can also be seen from Table XV, can amorphous MP in substance as a result of the vapor phase transport reaction produced v / earth. These pieces form in a narrowed section 160 of the reactor tube 132 (FIGS. 1 and 2) in the *,, arjüngten section 162 of the Reactor tube 58 (Pig, 3) or in zone 2 of the in Pig, 16 Device shown = All of these products show in the X-ray diffraction spectrum no definable reflexes =

To determine the degree of amorphicity of a material, X-ray diffraction diagrams are used, which are recorded with powdery substances. "These amorphous MP substances with χ much larger than 15 can be cut, lapped and polished using methods such as those from semiconductor technology are known per se for the preparation of chips _o This applies in particular to materials? which contain no more than 50 to 500 ppm metal and are in themselves a new form or modification of phosphorus »

The amorphous KP chips with a high value for χ are valuable semiconductors with electro-optical properties, the quality of which is practically identical to the data measured for KP. ^ - whiskers. From this it can be concluded that in all MP substances with χ = 15 or with κ much greater than 15p as long as the substances mentioned above are precipitated in the presence of an alkali metal, essentially all have the same short-range order type of structure and zvhblt over the entire material present. This short-range structure can be hollowed out by the parallel pentagonals Phosphor columns

BATH ORIGINAL

describe.

Amorphous phosphorus-rich KP material can be produced with mirror-polished surfaces in a quality that these materials can be evaluated electro-optically. The surfaces are routinely treated, For example, first cut, then embedded, then lapped, finally polished and chemically etched. Since the surface damage that occurs on the amorphous material during this process reduces the electro-optical performance affect the semiconductor material, the work of the applicant on processing methods and focuses on the development and improvement of such surface treatment processes that are largely "non-destructive" act on the surface. Have the surface finishing methods described in more detail below has proven itself particularly well for the amorphous KP material for the production of mirror-polished surfaces.

Embedded pieces KP with very large values of χ and lengths on the order of approximately 1 to 2 cm of the in The type described in TableSI are slow cutting speed and the smallest feed pressure cut with a diamond saw. Each slice has a strength of about 1 mm. The cut slices are immersed in a bromine-nitric acid solution. Be there Cuts removed and becomes the strength of the disc reduced to about 50 μΐη. The slices or Chips are then washed and examined for inclusions and voids. It turns out that the amorphous KP material with high x values is practically completely free of bubbles and voids.

A common low-melting wax with a melting point of approximately 80 ^° C. is used to hold the

KP chips on a pole. The slices will then

^x -1

lapped at a speed of 50 min in 2 nin intervals, individually with silicon carbide paste (400 and 600 grit) using distilled water as

Lubricant and under the pressure of a mass of

2 50 g / cm “Es wi can be obtained

2 50 g / cm “Lapping takes place until the surfaces are smooth

The chips lapped in this way are then polished for 1 hour at a speed of 50 - ", in a mass of 50g / cm ² with a 3 μm diamond duster and lapping oil as an extender." After this prepolishing step, an additional 15 minutes at 50 min "and 50g / cm ² polished with a microcloth, the polishing agent used is a cloud of aluminum oxide with a grain size of 0.05 μm in distilled water. Between each lapping step and grinding step, the chips are cleaned with the utmost care in an ultrasonic bath , then rinsed and dried »

The specimens produced using this process have high quality, mirror-like surfaces. The final polishing is carried out with common metallographic polishing devices (Buehler). _:

In the manufacture of chips, chemical etching plays an important role in the surface treatment, in the preparation of the components , in the metallization and in the final production of the components »

The chemistry and the practical aspects of etching processes are in countless articles of the chemical and technical Information about special etchants described in the literature is, however, widely scattered in the scientific literature » So it took considerable effort to research for etchants that are used to etch amorphous MP substances high phosphorus would be suitable. It was in particular

BATH ORIGINAL

Attention was paid to the treatment of the surfaces of such substances. Research into the literature and practical tests have shown the applicant that the etching solutions and methods which are currently used for etching GaP and InP ^- are most suitable for the MP - substances after appropriate modification. The following etching solutions were selected and tested:

- 5-10% Br ^ 95-90% CH ₃ OH for the purpose of general etching and polishing

- 1% Br ₂ , 99% CH ₃ OH for polishing high quality surfaces (approx. 1 μΐη / min)

- 5 wt .-% NaOCl solution for chemical polishing

- 1 HCl: 2 HNO ₃ (1% Br „) for removing machining injuries after cutting and lapping

- 1 HCl: 2 HNO ₃ for removing surface layers

A number of specimens for measuring optical absorption are produced. The process steps described above are used for cutting and polishing on both sides of amorphous chips made of material with high x values, the thickness of the test specimens being in the range of 0-5 mm. Reference specimens made of GaP and GaAs crystals are also polished on both sides and used for reference measurement of the band gap by optical absorption.

To uncover microstructures, special etching processes are being developed with which the chips are applied to small and Narrow areas are also etched down to a thickness of 0.2 mm to carry out optical absorption measurements could become.

Numerous etching solutions are selected and tested for this purpose. The best chemical solution was a mixture of 6.0 g of potassium hydroxide, 4 g of red potassium iron (III) cyanide and 50 ml of distilled water at 70 ^° C. The exposure time to make etching patterns visible is less than 60 seconds. The solution is unusually stable and can be used with easily reproducible etching data.

After embedding, cutting and polishing the amorphous KP specimens with χ much larger than 15 accordingly The etching tests were carried out on the substances listed in Tables VII and VIII. Typical microstructures became visible after 30 seconds with this etching process.

In Fig. 21 is a photomicrograph enlarged 360 times showing an etching pattern on a surface perpendicular to the axis of the amorphous pieces of the phosphorus-rich material shows that after the swelling vapor phase transport process (Experiment No. 28 in Table VII) has been received. Honeycomb-like microstructures with distinctly well-defined areas can be seen in the etched pattern, the extent of which is a few µm. These honeycomb-like Microstructures are typical for etched patterns on materials with a two-dimensional atomic lattice (such as parallel columns) "

In FIG. 22, the microphotograph is enlarged 360 times of an etching pattern on a surface that is perpendicular to the growth axis of the amorphous Phosphorus-rich material prepared by the two-source vapor phase transport method in Example 6 is cut has been. FIG. 23 shows a photomicrograph of the same etched surfaces as that shown in FIG Surface, but at 720x magnification. Fig. 24 is a photomicrograph enlarged 360 times

an etched surface perpendicular to that in the figures 22 and 23 and shows etch patterns typical of column packs.

The results of these etching experiments show that the MP material, where M is an alkali metal and X is much greater than 15, i.e. for material in which the alkali metal concentrations are in the range of 50 ppm, have short-range regions that are parallel to each other Pentagonal phosphor columns are marked, whereby the columns which are parallel to one another are either all parallel (MP .. ₅ shape) or form double alternating layers perpendicular to one another (monoclinic phosphor).

The electro-optical determination of characteristics is carried out on single crystal whiskers, performed on polycrystalline layers and amorphous layers as well as on pieces. The markings consists of (1) optical measurements on specimens without electrical Contact (absorption edge, photoluminescence); (2) electrical measurements with simple contacts and linear Transition behavior (conductivity, temperature dependence of Conductivity, photoconductivity, wavelength dependence of photoconductivity, conductivity type); (3) electrical Measurements with non-linear or rectifying contact transitions with metals that indicate semiconductor behavior.

From the above measurements data are compiled, showing that all of the substances produced meet the electrical requirements for industrially useful semiconductors, that is, all substances have a band gap in the range of Ibis 3 eV, have a specific electric conductivity ranging from 10 ^-5 to 10 ~ ¹² (ohm-cm) " ¹ have a photoconductivity ratio (conductivity under exposure to dark conductivity) of 100 to 10,000 and, moreover, have chemical and physical

Stability under normal '= "ambient operating conditions, The measurements are carried out with the following devices:

(1) Absorption edge Zeiss, 2-beam spectrometer,

IR and visible.

Photoluminescence in the cryostat at low temperatures

(4 K) r laser excitation

(2) specific electrical conductivity; 2-probe measurements and 4-probe

Measurements

Temperature dependence of the specific

Conductivity: Measured in the range from 300 K to

550 K in an evacuated chamber.

Photoconductivity Measured with a light source of

about 100 mW / cm ² .

Wavelength dependence of the photoconductivity: Xe lamp as a light source in conjunction with a monochromator "

Conductivity type by measuring the thermoelectric

Force with a hot and a cold probe

(3) Silver contact paste is used to make temporary contacts to the material with an am photovoltage of 0.2 V measured in an open circle under exposure.

BATH ORIGINAL

Metallic contacts and press contacts, which formed junctions and barrier layers, are determined with regard to their current-voltage characteristics on a Tektronix waveform recorder recorded.

The data of the results obtained on the samples of a wide class of substances are in Tables 16, 17, 18 and 19 summarized.

Table 16 shows the most important basic physical, chemical and electro-optical characteristics of the Material prototypes summarized, namely from KP with χ in the range from 15 to much larger than 15, in different physical forms and chemical compositions. -

Table XVI Typical data for material obtained after the swell-in seed phase transport reaction from K / P "feed

Properties single crystal (KP ₁₅ ) polycrystalline (ΚΡ _χ ) amorphous (ΚΡ _χ )

electro-optical

special Conductivity 10 ~ ^ «= 10 ' ⁼ ' ^ 10 ° -10 IQ

(ohm-cn)

Photoconductivity 1Q ² = 1Ö ⁴ 10 ² 19 ι

(Light / dark) '

O photoconductivity- I ₀ 4 = 1. SeV I.4-lo8 © V Io4-ll

O maximum shark

Q activation energy (2E)] U2 @ V l, 4eV leieV

^ From Temp Abhang.der "

f "Le ^ cability

Absorption I ₀ SeV l <.4e ¥ ---.-

edge

Luminescence, ^ g _e y ._> _ —_.

4 ° K

Luminescence, I ^ 7eV 1.7eV

300 ⁰ K η-Type n-Typa

Type - 0.2eV —.—

Photo voltage (open circle) volts

· ■ QQ CJ)

Table XVI (continued) Typical data for material obtained after Einwellendanpfphaser.-Transport reaction from K / P "feed

properties

Single crystal (KP-)

Polycrystalline (KP.)

Amorphous (KP)
χ * 15 ^X

Thermal

DTA (Sharp, -endothermic) 630 ° -1. Warming

6 3 0 ° C-2nd heating

TGA

450 ⁰ C

Decomposition temp.
(Mass spectrometer) 450 ⁰ C 400 ° C / 3h Stable up to 450 ⁰ C

Chemical resistance

Room temp .; 3h

85% H ₃ PO ₄ , 95% H ₂ SO ₄ stable

50% HF, 37.5% HCl, 50% NaOH

Boiling

1h

stable stable

615 - 1st warming 590 - 2nd warming

Stable up to 400 ^° C

stable

stable stable 590 - 1st warming
590-2. Warming

Stable up to 350 ^° C

stable

stable
stable

I,

Assessment of stability according to opt. impression

DTA) differential thermal analysis

TGA) thermogravimetric analysis CO

OO

cn co

. / S

a-

Table XVII shows the properties of the alkali metal polyphosphides of various compositions and physical forms. These characteristic data surprisingly show that the electro-optical properties of the substances are independent of the metal, that is to say that largely the same values are obtained for lithium, sodium, potassium, rubidium and cesium as the metal of the polyphosphides. The electro-optical characteristics are also independent of the physical form, i.e. crystalline, polycrystalline, amorphous as fitting or amorphous as a piece, and in which chemical composition, ie x = 15 or χ very much greater than 15 =

Table XVII

Polyphosphides - structural and electro-optical properties A = diagram similar to KP _1c B - diagram similar to KP with χ SS>

material

M = K

crystalline polycrystalline amorphous

M = Na

crystalline polycrystalline amorphous

M = Rb

crystalline polycrystalline amorphous

M = Cs

crystalline polycrystalline amorphous

Chemical Analysis

Roentgen-

diffractive

diagram

specific electrical conductivity (OHM · CM) "'

Photoconductivity
relationship

15 B 15 amorphous

NaP

15th

NaP "x» ₁₅ β NaP

χ »15 amorphous

RbP ₁₅

CsP

15th

^o : ₇ ¹⁰

10 " ⁷ -10 ' ⁸

10 " lof-io ³
io |

¹⁰ I 2 lOj-10 ²

Band gap (eV)

1.8

1.8-2.0

1.8-2.0

1.8 1.8 1.8

1.8

1.8

In Table XVIII sin-? the properties more mixed Polyphosphide compiled. The characteristics show that the mixed alkali metal polyphosphides also have practically no changed characteristic data and the alkali metal mixture also has no influence on the characteristic data Has. A partial substitution of arsenic on phosphorus sites can be carried out and leads to a reduction in the specific electrical resistance and possibly also to a reduction in the distance to the wall, which is typical for - ^ ne substitution doping.

BATH

Table XVIII

Mixed polyphosphide electro-optic properties

material

Output X-ray special conductive photoconductive substances diffraction slide ability ability

gram

(ohm cm) -1 ratio

K Na ₁ P
γ 1 -y χ Kl ₂ Z ^ l ₆ O A. io- ⁸ -io- ⁹ crystalline ^K 6 ^{/ Li} 2 ^{/ P} 80 A. ΙΟ " ⁹ π K Li ₁ P
y 1-yx
crystalline ι ORI Na Rb ₁ P
y 1-y χ NaZRbZP ₃₀ A. 10 " ⁸ O
1 crystalline NaZRbZP ₃₀ amorphous ΙΟ " ⁹ amorphous KZAs ₂ ZP ₁₃ A. ΙΟ " ⁹ K As P
y ζ xz
crystalline KZAs ₂ ZP ₁₃ amorphous ΙΟ " ⁷ amorphous K As P
y ζ xz KZAs ,, ZP. A. ΙΟ " ⁹ crystalline

10 '10' 10 '

10

10 '10'

Band gap (eV)

1.8-2 1.8

1.8 1.8-2

1.8

• 1.6

1.8

A = diagram resembles crystalline KP

15th

- As'S -

Table XIX summarizes the properties of various substances that have been produced on the basis of different ratios in the starting batches. The characteristics show that the. ¹ best properties can be obtained with substances prepared from feeds in which the ratio of P to K is approximately 15, generally in the range of approximately 10 to 30. Below a P / K ratio of 10 the yield decreases . Above a P / C ratio of 30, the physical properties of the amorphous pieces begin to deteriorate.

Table XIX

KP from different starting substances, analyzed in

Tables IX, X and XI

Starting
material Chemical
analysis Roentgen-
diffractive
diagram special el.
Conductive
speed
(ohm-cm) Photoconductive
ability
₁ ratio K / P reagent
crystalline
polycrystalline χ - 15
X »15 A.
B. 10 ~ ⁸ -10 ~ ⁹
-7 - Q
10 -10 10 ² -10 ³
ίο ² amorphous x »15 amorphous io " ⁸ -io- ⁹ 10 ² K / P _{15 in}
crystalline χ «15 A. ίο " ⁹ 10 ² polycrystalline x »15 B. ίο- ⁸ 10 ² amorphous x »15 amorphous 10 " ⁸ ίο ³ KZP ₃₀ crystalline χ - 15 A. ΙΟ "' 10 ² polycric istallin x »15 B. ΙΟ ' ⁹ 10 ² -10 ³ amorphous x »15 k / p ₅ crystalline χ - 15 A. ΙΟ ' ⁹ 10 polycrystalline x »15 B. «Γ ⁸ . 10 amorphous ^{K / P} 125 crystalline
polycrystalline
amorphous χ »15 bad phys.

properties

A = diagram resembles crystalline

B = diagram resembles crystalline KP

ORIGlMAt BATHROOM.

The data show that all substances, no matter what Form they are present, have a band gap in the range from 1 to 3 eV, in particular in the range from 1.4 to 2.2 eV, since 1.4 eV is the lowest photoconductivity maximum measured and 2.2 eV is the estimated one Band gap of the red phosphorus is »These data also show that the band gap of the best form of the substances is around 1.8 eV “It is also astonishing that the high conductivity ratio"? ■ * - "is of the substances in the from 100 to 10,000 and also suggests that the polyphosphides of the invention are excellent semiconductors are.

Amorphous MP ^ pieces produced by the single source vapor phase transport method (Tables VI, VII, X and XI) have been produced in the three-zone furnace and x values are much larger than 15 can be cut, lapped, polished, and etched, ultimately creating chips with a diameter of about 0.5 cm can be obtained with mirror-finish surfaces.

The electrical measurements on these samples are different geometrical arrangements of the electrical contacts for the exact determination of the specific electrical Conductivity of the massive material has been carried out. The measurements are made with two and four probes. the Overall measurement results have confirmed that the true

specific substance conductivity of the materials at 10

- 9 - 1
up to 10 (ohm ° cm). This specific electrical

Conductivity is too low to have sharply defined transitions to generate with equalization properties = It was therefore important to To find doping elements with which the mechanism of the electrical conduction in the substances is so influenced and the specific electrical conductivity so increased it can be said that efficiently working transitions can be created. As is the case with other amorphous semiconductors

BATH ORIGINAL

is typical, the specific electrical conductivity is not influenced by lower proportions of foreign substances in the material. For the amorphous material according to the invention, intrinsic conduction is observed above room temperature with an activation energy which is approximately equal to half the band gap _r, which in other words means that the Fermi level is approximately in the middle of the band gap. The low electrical conductivity and the high photoconductivity ratio indicate that the material contains unsaturated open bonds in low concentrations. This further indicates that a strong disturbance of the electron wave functions of the PP bonds is required in order to influence the specific electrical conductivity of the material and to change the conductivity type.

To this end, two paths are taken: (1) On the one hand, arsenic or bismuth are substituted on phosphorus sites, (2) on the other hand, foreign elements are diffused into the amorphous matrix.

According to the first method, arsenic is built into the matrix, whereby products of the type K / As ₂ / P _ are obtained. By this measure, the specific electrical conductivity can be improved by two orders of magnitude (Table XVIII), while the substance remains an n-conductor.

Numerous conventional diffusion dopants such as Cu, Zn, Al, In, Ga and KI in the vapor phase, as Liquid and tried unsuccessfully by diffusion in the best condition. To the great surprise, pose yourself then the success one in the diffusion of nickel and iron

BATH

• 13-5 "" -

and chromium, the diffusion being carried out in the solid state. For example, a nickel layer is applied by vacuum vapor deposition to a carefully prepared surface of a KP chip with high x values. «The structure is heated for a few hours. Here, a nickel diffused about 0 _f 5 microns deep into the substrate. This led to an improvement in the specific electrical conductivity of more than five orders of magnitude = the substance is still n-conductive.

In detail, a 150 nm thick nickel layer is applied to a chip in a resistance-heated Vacuum evaporator evaporated under a pressure of 10 mbar (evaporation system from Varian).

The test specimen is melted in an evacuated Pyrex glass ampoule and ^{heated to 350 °} C. for 4 hours »

- / Go -

The nickel cover layer is then removed. The electric The conductivity of the test object is measured using the two-probe method. This shows that the specific electrical

-8 -4

see conductivity improved from 10 to greater than 10 Has. Electrospectroscopic analysis (ESCA) of the depth profile of the sample shows that the diffusion depth is 0.4 µm and that the nickel is present in the material as Ni, i.e. as free nickel. The wave function of the nickel overlaps the wave functions of the electrons of the P-P matrix and thereby impaired by an improvement in the charge carrier mobility the specific electrical conductivity. The nickel concentration in the sample is greater than 1 atom%.

With gold vapor deposition and dry silver paste for coplanar Order, ohmic contacts are obtained on the doped layer.

Changes in the diffusion temperature show that a temperature of 350 ^° C. is to be regarded as the optimum temperature for the nickel diffusion.

Systematic changes in the duration of diffusion show that diffusion strictly follows the classical law of diffusion, that is, the diffusion depth is proportional to the root of time. If a 150 nm thick nickel layer heated for 60 h at 350 ⁰ C, a diffusion depth of 1.5 is measured μπι according to the ESCA method. A temperature of 3 50 ^° C. approaches the uppermost temperature limit to which the amorphous substances can be exposed.

The nickel diffusion can also be effected from the liquid phase, for example from a Ni-Ga melt or can from the Vapor phase, for example using nickel carbonyl, can be effected.

The tests have also shown that iron and chromium show a doping behavior that is similar to that of nickel is similar, but the same procedures can be used with iron and chromium as with nickel,

For example, a chip was cut from an amorphous, high phosphorus (large x) piece made by vapor phase transport using a single source. A 50 nm thick fiselayer was evaporated onto the cut chip. Subsequently, the iron 16 is diffused h at 35O ⁰ C in the chip. When measuring with 2 pressure electrodes, a completely non-linear characteristic is measured for the doped material (Tektronix curve recorder).

On another chip of the material with high x-value 30 nm 20 nm of nickel and iron are deposited "The layer structure is heated to 3 50 ⁰ C then 16h. Subsequently, aluminum contacts 200 nm thick with a radius of 1 mm are vapor-deposited. The current-voltage characteristic between the aluminum contacts is then measured. Completely non-linear characteristics are obtained.

On a further chip made of material with a high λ value, produced by a source-vapor phase transport reaction, 50μΐη nickel-chromium alloy is vapor-deposited. The chip is then heated ^{to 350 °} C. for 16 h for diffusion. Subsequently, aluminum contacts with a radius of 1 nftn and a thickness of 200 nm are vapor-deposited onto the chip. Again, completely non-linear current-voltage characteristics are obtained between the two aluminum contacts.

The experiments show that nickel, iron and chromium are effective diffusion agents for the substances of the invention that noticeably improve the specific electrical conductivity, namely

Λ * ·

improve so that barrier layer transitions with silver contact paste, can be made by pressure contacts and with aluminum contacts.

Other elements besides nickel, iron and chromium with occupied outer d-shells or f-shells that overlap the phosphorus levels are also potential dopants with which the specific electrical conductivity of semiconductor materials can be changed according to the invention so that the substance becomes p-conductive and is capable of p / n junctions form, which are a prerequisite for the manufacture of semiconductor components.

According to the process of the two-source vapor phase transport reaction become two different types of amorphous phosphorus-rich substances manufactured whose properties are measured below and are described. .

(1) Amorphous KP pieces (Example VI) with χ approximately = 50 on one Side and χ much larger than 15 on the other. The surface analysis supports the assumption of a matrix effect, which is particularly pronounced in this process. The surface of a cut and polished test specimen is of the best quality and has only a very small number of imperfections and voids and shows homogeneous etched images.

The specific electrical conductivity is determined by the. , Two-probe method determined to be 10 (ohm cm). The photoconductive

Ability ratio under exposure to 100 mW / cm is greater than 10. The photoconductivity maximum occurs at approximately 1.8 eV and thus indicates a band gap of this order of magnitude. The data also show that the P-P bonds determine the electrical and optical processes in the crystal and determine the characteristics of the material as well as those in the

Properties described in Tables XVI, XVII and XVIII and XIV, as well as the large value of the photoconductivity ratio, all of which indicate a greatly reduced concentration of open valences.

(2) Thin amorphous layers of KP _ (Experiment No. 47, Table XII) which are deposited on a small glass plate which has previously been vapor-deposited with a metal layer. The metal layer serves as a rear contact for the thin amorphous layer. The success of this production of thin precipitation _{layers of KP 15} opens the way for the technical production of a wide variety of thin-film components.

Thin amorphous KP ₁ r layers, which are deposited by the two-source method, have thicknesses in the order of magnitude of approximately 0.5 μm and areas of approximately

3 cm. The layers are homogeneous, the surface roughness of such layers not exceeding 200 nm. The deposited layers are chemically stable. FIG. 25 shows a photomicrograph, magnified 2000 times, of such a KP ₁ c layer. The adhesion of the layers to the substrate is excellent. The quantitative analysis of the layers with the aid of the scanning electron microscope and the X-ray scattered radiation measurement show that the di-3 composition of the layers corresponds to _{the nominal composition KP 1 1-.} The layers have a homogeneous distribution of the composition, are dense and have no pores or scars that lead to the surface. The surfaces are perfectly flat and uniform, of electro-optic quality, over the entire surface of the layers.

In view of the fact that nickel diffuses into CP pieces, the following experiment is carried out: in the one shown in FIG

In a schematically illustrated manner, a nickel film 172 is evaporated onto a glass substrate 170 in order to form a rear contact for an amorphous KP ₁ c layer 174.

The nickel simultaneously serves as a rear electrical contact for the layer and as a diffusion agent. Profile investigations according to the ESCA and SEM methods show that the nickel _{diffuses to a considerable extent into the KP 15} layer 124, specifically at a speed of 20 nm / h during the growth of the KP ₁ ^ layer.

In detail, a nickel layer 172 with a thickness of 150 nm is produced by vapor deposition in a vacuum at 10 mbar evaporated onto the surface of the glass plate 170. Part of the nickel surface is then coated with a tantalum layer masked to create material-free areas for electrical contacts.

2 μΐη amorphous KP ₁ , - 174 are then applied to the nickel layer 172 in a two-source reactor. The composition of the deposited layer is used as KP ₁₁ - identified. The layer is amorphous and contains 1% of diffused nickel.

A pressure contact with an electrical probe is placed on top of the KP ₁ , - "layer. Supply lines from the rear surface contact and from the top-side pressure contact are connected to the Tektronix -» curve recording device 176 so that the current-voltage characteristics can be read directly. The conduction characteristic of the rectifying pressure contact junction (tip junction) is shown in FIG. 27, whereby it can be seen from the curve shown that the barrier layer has a threshold height of 0.5 eV with a current in the mA range.

In the manner shown in FIG. 28, a copper contact 178 with a radius of 2 mm is also deposited on the upper surface 180 of the amorphous KP by vapor deposition in a vacuum. [- Vapor-deposited layer 182, which is deposited on a nickel layer 184 using the two-source method, "the nickel layer itself being vapor-deposited onto a glass substrate 126". The Tektronix characteristic curve recorder 176 is connected in the manner indicated schematically in FIG. With this device, the full current-voltage characteristic is recorded in the forward direction and in the blocking of the junction. The characteristic curve is shown in Figure * 29 * The curve shows that s copper with the materials non-linear barrier layer contacts forms "

Smaller metal points are then deposited as top-side contacts in order to reduce the influence of the leakage currents and to switch off leakage currents at the contact edges. In this way, mechanical masks are used in a vacuum 10

2 -5 %

cm area contacts and 10 cm tip contacts vapor-deposited onto the surface. The current-voltage characteristics this arrangement are made with copper electrodes, gold electrodes and aluminum electrodes were measured. The characteristics are shown in FIG. 31. The characteristics show in each Case the characteristic curve for breakdown voltages of two anti-parallel connected diodes. Similar curves be used for winding ,. Titanium, Magnesium and Silier as the top contacts obtain.

The most significant difference occurs in the fact that gold contacts the Stroxn voltage characteristics after applying Change 10 V to the component. The current-voltage characteristic becomes asymmetrical in the manner shown in FIG. 32, having a more ohmic characteristic Contact at the gold phase boundary can be obtained after this formation process ". Such a" formation "is

continuously observed for gold and is occasionally also measured for silver and copper as tip contacts. The formation does not permanently affect the component, but occurs again every time a voltage is impressed. Heating of the element to 300 ⁰ C not bee influßt this effect. Cooling the element to -20 ⁰ C resulting in the formation significantly kinked current-voltage characteristics (FIG. 33).

It appears that the "formation" was a breakdown of a high resistance layer that was diffusing in Part of the device and the upper contact remains or is obtained. The capacitance-voltage (CV) characteristics are shown in Figures 34, 35 and 36 point in the same direction. Al and Au top contacts have CV characteristics of double diodes. In the case of Au contacts, however, these change in individual diode behavior. Provided one assumes a dielectric constant of about 10, one can from this a carrier concentration of approximately 10 carriers per cm near the transition and a wearer mobility

- 2 2
from approximately 10 to 1 cm / Vs. The frequency dependence of the capacitance and the resistance according to FIG. 37 can be used to produce or simulate the multiple transitions or many transitions that build up in such a structure with a graded diffusion profile in the active material. The quality of the depletion material (low density or doping) and the rough surface morphology could also contribute to the complex observations. Nonetheless, the ability to form transition formations was demonstrated _{on 2 source thin film KP 15.}

Some of the phenomena mentioned above, such as the "formation" with Au contacts, also occurred with rapidly evaporating thin films observed that were deposited on Ni. This layer is not a pure CP. , - "layer, but has excellent

¹ V--

Qualitative features »In this case, no capacitance-voltage dependency was found. The very thin device showed good light behavior and a relatively small current (10 A) could be drawn under short-circuit conditions when the device was illuminated with visible light.

One can expect that KP ₁ ^ thin films produced by means of CVD techniques show a similar behavior if these films are sufficiently thick. At present these layers are still at & * ' ^ n and bridges or short circuits have been found.

The formation of transitions with these materials indicates this indicate that they can be used to form pn junctions, Schottky diodes or metal oxide semiconductors (MOS).

One can expect that using the above-mentioned classes of dopants will lead to the p-type conductivity materials and in this way can be used in your extensive field of semiconductor technology.

In all of these cases, the photoelectric conductivity ratio became achieved by manufacturing a semiconductor device that contained our material and contacting devices, which were attached to the material in order to establish an electrical connection with it »This device comprised two single electrodes 80 and 82 that were placed on the material 30 were applied.

Seen in more detail, two copper strips 80 and 82 were attached to a glass substrate 84 in an adhesive or adhesive manner for a single crystal made of MP _{1 ^.} A copy of a KP. "Strip 86, which had been made in accordance with the preceding teachings, was placed over one end of the strips 80 and 82 as a bridge and attached to it by means of a silver paste 88.

BATH ORIGINAL

■■ * ■

An electrometer was connected to the opposite ends of the strips 80 and 82, which applied an electrical potential to the KP ₁ strip via the copper strips and thereby enabled the resistance of the KP ₁ strip to be measured.

The arrangement resulting from FIG. 30 and the corresponding description and similar arrangements to our Other materials used strengthen the view that the phosphor materials provided with high phosphorus contents actually for the control or control of the electric current and at least as light sensitive Resistance element can be used.

In addition, our materials show luminescence properties with an emission peak at 1.8 eV at temperatures of 4 K and luminescence even at ambient temperatures.

To make large crystals of monoclinic phosphorus rubidium:

₁₅ can be used to make large monoclinic phosphor crystals.

0.62 g of a sample of RbP ₁₅ encapsulated in a vacuum is placed vertically in a muffle furnace. The ampoule has an outside diameter of 10 mm, an inside diameter of 6 mm and a length of 5 cm. The vertical quartz ampoule is exposed to a temperature profile in the manner that the RbP ₁₅ is held feedstock at a temperature of 552 ⁰ C, while the tip of the ampoule is maintained at a temperature of 539 ⁰ C. The residence time of the ampoule with the load at this temperature is 22 hours. Then the ampoule is opened and large monoclinic phosphor crystals with edge lengths up to 3.0 mm with the habit of a pyramidal

blunt in the upper, cooler section of the ampoule found.

These large monoclinic phosphor crystals can also be produced from mixtures of rubidium and phosphorus in a molar atomic ratio of 1s15 (RbP ₁₅ ) »

Large monoclinic phosphor crystals can also be produced via vapor phase transport both starting from CsP ₁ , - and starting from NaP ₅ as a charge / where • ii-3 starting substances are produced by solid-state reaction. In each experiment, approximately 0.5 g of the corresponding alkali metal polyphosphite is melted in vacuo in a quartz ampoule (10 mm outside diameter, 6 mm inside diameter) which has a length of 8.9 cm. The vials are then subjected to a temperature gradient in the manner that the Älkalimetallpolyphosphidbeschickung is maintained at a temperature of 558 ⁰ G, while the tips of the ampoules are kept at a temperature of 514 ⁰ C. After a residence time of 18 h at this temperature profile, dark red crystals in the form of stacked square platelets are found, ax * identified as monoclinic phosphorus obtained from the CsP ₁ charge. The morphology of these monoclinic phosphorus single crystals, which are produced from CsP ₁ J. and NaP ₁ , - which in turn were initially produced by solid-state reaction, are very similar to one another, that is, when NaP ₁ r is used as the starting substance, they are stacked square platelets obtained as crystal yield »This crystal shape deviates from the habitus of the truncated pyramid _r that shows the monoclinic phosphorus, which is obtained from a RbP ₁ ^ charge. Large monoclinic phosphor crystals can also be obtained from Cs / P ^ and Cs / P. ,, - Cs / Pj ₅ mixtures if these substances are exposed to higher temperatures.

BATH

- yer -

Monoclinic phosphor single crystals can also be produced from KP ₁ ^, which is initially produced by solid-state reaction. _{The monoclinic phosphor crystals} can also be obtained from mixtures of K / P 3Q and K / P ₁₂₅ .

No experiments have been carried out with lithium, i.e. with lithium / phosphorus charges. It can, however expect large monoclinic phosphorus single crystals with such feeds, too, if similar Reaction conditions are available.

While the type of alkali metal used does not appear to be particularly critical for this crystal growth, the temperature at which the charge is maintained is evidently of greater importance to crystal growth. In the case of the feed CsZP _11, wherein the feed has previously been ground in the ball mill and mixed, large single crystals are obtained when the feed is maintained at a temperature in the range from 555 ⁰ C to 554 ⁰ C. If the feed is kept at temperatures around 565 ⁰ C or 554 ⁰ C, no big monoclinic Phosphoreinkristalle more can be produced.

The apparatus preferably used with which the experiments are carried out is shown in FIG. 38. _{RbP 15} produced by solid-state reaction in an amount of 0.6 g is melted in vacuo into a glass tube 270 which has an outer diameter of 12 mm, an inner diameter of 6 mm and a length of 8 cm. The top of the glass ampoule is melted off in such a way that a flat glass surface 272 measuring 16 mm in diameter is obtained. A single nozzle 274 is provided with a constriction 276 at which the ampoule is melted off after loading.

The ampoule filled and melted in this way is exposed to a temperature gradient in such a way that the flat surface 272 on the upper section of the ampoule or the reactor ^{tube is kept at a temperature of 462 °} C., while the charge at the bottom of the tube is kept at a temperature of 550 ⁰ C is maintained = after a dwell time of 140 h at this temperature, approximately half of the originally given charge has been transported from the bottom to the upper surface «

As a product, a button-like substance piece is obtained which split and is checked. This piece of substance consists almost exclusively of homogeneous, light red fibers and not the large monoclinic phosphorus monocrystals that are actually expected. In Figures 44 and 45, scanning electron microscope images of this product are shown in 200-fold and 1000-fold magnification »

The scanning electron micrographs in FIGS. 44 and 45 are a real surprise. Individual "fibers" exist from bundles of elongated platelets which are brought together so that they have star-shaped rods in cross-section when seen from the side. This material is markedly different in appearance from the Twisted rods or pillars of fibrous phosphorus formed by vapor phase transport from 99.9999% pure red phosphorus can be obtained (see below).

Do these attempts show? that a temperature in the range of 500 ⁰ C to 560 ⁰ C should be maintained for the production of large monoclinic phosphor single crystals. Further experiments show that the condensation of phosphorus should lie in the preparation of monoclinic crystals is preferably about 539 ⁰ C.

The charge must be heated to a temperature of greater than 545 ^° C. and less than 565 ^° C., as the experiments described above show. The charge is preferably heated to a temperature in the range from 550 to 560 ^° C., a temperature of around 555 ^° C. for the production of monoclinic phosphorus monocrystals giving the best results.

Monoclinic phosphorus is made from feeds with different ratios of phosphorus to alkali metal this ratio being varied in the range from 11: 1 to 125: 1. The best results however, are obtained at a phosphorus to alkali metal ratio of 15: 1.

39 shows the photomicrograph of a truncated pyramidal monoclinic phosphor crystal, which is made up of an RbP. ₅ loading has been established. These crystals are difficult to split. Similar crystals are obtained when sodium is used as the alkali metal in the feed. The crystals have dimensions of up to 4 mm 3 mm 2 mm.

In Fig. 40, enlarged 80 times, is the photomicrograph of a monoclinic phosphorus single crystal is shown, which consists of a mixture of Cs / P ... has been received. These platelets are light to split and their physical behavior is reminiscent of mica flakes. Similar crystals can also be made from Charges from K / P .., - are made. Crystals with This habitus was obtained with edge lengths of up to 4 mm and with thicknesses of up to 2 mm.

The crystals show birefringence. When the crystals are placed between crossed polarizers in a polarizing microscope

■ ί · »

are brought, they rotate the plane of polarized light and only partially let the light through. Such crystals can be used as birefringent elements, for example in optical rotators, in the red and in the infrared region of the spectrum «

Chemical analysis shows that the crystals are approximately 500 Contains up to 2,000 ppm of alkali metals »They let themselves through produce a process that does not exceed 22 h in total requires. This is a ^ - Lstep if, on the other hand, the procedural time of 11 d is taken into account, which are state-of-the-art for the production of Hittorf's phosphorus.

X-ray diffraction diagrams are recorded from powder samples. those with the Hittorf's phosphor according to the state of the art to match"

The photoluminescence spectra are shown in Figs. The spectra shown were recorded with an argon laser in the Raman spectrometer. A broad maximum at 1.91 eV is clearly pronounced with a half-value width of approximately 0.29 eV. These data suggest a band gap of about 2.0 eV at room temperature *

The spectrum shown in Fig. 41 is produced using a monoclinic phosphor single crystal shown in Presence of Cesium has been bred. In contrast, the spectrum in FIG. 42 shows a monoclinic phosphor single crystal, which has been condensed in the presence of rubidium.

The Raman spectrum shown in Fig. 43 was recorded using a monoclinic phosphor single crystal, made in the presence of rubidium. The maxima 280 to 285 are used with wave numbers of 285, 367,

BATH ORIGINAL

465, 48 3 and 52 9 cm observed.

Evaporated swabs with diameters in the range of 25 .mu.m are applied to large monoclinic phosphorus single crystals which had been obtained _{from a RbZP 1, .- source.} The phosphor single crystal surfaces contacted in this way are subjected to the electrical resistance measurement. The crystals showed an electrical resistance in the range from 10 to 10 ohm, almost independent of the geometry of the crystal and the dimensions of the contacts. This can be interpreted to the effect that the measurements reflect surface resistances.

The crystals can serve as a substrate for the deposition of III-V semiconductor material, for example indium phosphide or gallium phosphide. The crystals can continue as luminescence phosphors in display devices, as semiconductors, serve as lasers and as starting substances for the production of further semiconductor components.

The presence of alkali metal in the feed appears to be critical for the production of large crystals of monoclimatic phosphorus. An attempt was made to grow large single crystals of phosphorus with a monoclinic structure from 99.9999% pure red phosphorus by repeating reaction conditions which had been tested very successfully for a wide variety of alkali-metal-phosphorus systems. However, these attempts failed altogether. No monoclinic phosphor could be obtained in this way. For example, 0.6 g of a sample of 99.9999% pure phosphorus was heated to 552 ° C. in a melted ampoule that was placed vertically in a muffle furnace. The quartz ampoule had an outer diameter of 10 mm and an inner diameter of 6 mm. The temperature gradient between the bottom of the ampoule and the tip of the ampoule, which was 7 cm long, produced a temperature difference of 4 3 ^° C. After a residence time of 24 hours in this temperature gradient

more than half of the load had been transported into the upper third of the standing ampoule, where the substance was as a piece.

Surprisingly, however, this piece of substance exists entirely of red fibrous material. Some long about 1.5 ram long fibers are in the vapor space at the bottom of the piece of substance stuck to the tip of the ampoule. Microscopic examination of the deep red Fibers shows that the fibers are twisted as a whole.

Powder radiographs of the fibrous material show that they resemble the polycrystalline KP spectra recorded earlier with x values much greater than 15. 46 shows a scanning electron micrograph of these fibers magnified 500 times.

The differential thermal analytical data are similar to the data for polycrystalline material with high x-values in the system MP were obtained "The DTA -Untersuchungen showed a first heat plateau in the form of a single endothermic Niveausbei 622 ⁰ C (on average). A second heat plateau consists of a single endothermic level in both cases at 599 ⁰ C. The previously recorded on polycrystalline material with large x values DTÄ data secured for this material a first non-delaminated endothermic plateau at 614 ⁶ C and a second ,, also not splitted endothermic heat plateau at 590 ⁰ C in other words, the DTA studies on the twisted fibers exhibited as obtained for fibrous phosphorus in essentially the same results, consisting of 99.9999% pure red phosphorus and polycrystalline phosphorus-rich material of the system MP are obtained »stable thin layers in the form of amorphous coatings on glass and nickel-coated glass as

BATH ORIGINAL

Substrate material can be produced using the rapid evaporation method ("flash evaporation"). An apparatus with which such rapid evaporation can be carried out is shown in FIG. 47. The evaporation device 302 consists essentially of a glass cylinder 304 /, which can be connected via a line 306 to a vacuum system not shown in the figure. The inlet connection 308 is charged with argon via a supply line 310. A reservoir 312 is charged with powdery KP ₁₅ which has previously been produced by solid-state reaction. A vibrator 314 is used to move the load. The agitated feed is then entrained by the argon stream via venturi 316. The entrained feed material then passes into the reactor 304, via the feed line 317 into a steel vessel 318. The steel containment vessel 318 is heated by a high frequency coil 319 to a temperature of at least 900 ⁰ C, the KP entrained in an argon stream evaporates instantly _15th At the end of the line 317, nozzles 320 with several small openings 321 are arranged in the manner shown in FIG. 38 by inserting several narrowly scaled tubes. Line 317 and tubes 320 are made of alumina, with tubes 320 anchored in tube 317 with magnesia cement 322.

During evaporation, the KP- ₅ dissociates into its components. The vapor formed in this way is carried out by the argon through the nozzle-like openings 321. The product layer is then deposited on a cooler substrate 324 arranged in front of the nozzles. The substrate can be heated with the aid of heating wires 326, which are fed via electrical connecting wires 328. The alumina tube 317 has an outside diameter of about 0.64 cm and an inside diameter of about 0.32 cm. The tubes 320 each have an outside diameter of approximately 0.16 cm

and are approximately 1/4 inch long. They have little through Drilling.

The system is operated in a vacuum at pressures of 0.1 to 0.9 mbar. Amorphous layers with a thickness of up to 1 μm can be obtained when the system is operated for a maximum of 15 minutes. At the end of each run, the substrate 324 reaches a temperature of 200 to 300 ⁰ C, depending on what temperature thereof ,, the substrate at the beginning of the low ^ is ohlagens, or whether it vorgeheizt.ist to 200 ⁰ C at room temperature .

Thin KP ₁ layers are also produced by chemical reaction in the vapor phase with subsequent deposition of the product (CVD).

A typical CVD reactor is shown in FIG. The reactor is made of Pyrex glass. The reactor chamber 401 has an outer diameter of 26 mm and is 27.0 cm long. Inside the reactor, a long pipe is arranged., On the central axis of the reactor, which has mm an internal diameter of 6.0 and is 30.0 cm long. This long tube 402 serves both as a heat source and as a substrate holder. The heat source is held in position by an adjustable O-ring collar 403. A vent tube 404 enables a flue gas to be continuously withdrawn. It is connected to a cold trap, not shown in the figure, in which the unreacted phosphorus is precipitated before the extracted gas stream is fed to the surrounding atmosphere. Ring and an inner diameter of 2.0 cm connected to the reactor chamber 401. The reactor chamber 401 is placed in an electrical resistance heating furnace 406.

Melted phosphorus is not shown in the figures with a piston pump via a capillary 407, the one Inside diameter of 1.0 mm is measured into the evaporation chamber 408. The melted phosphorus is in the evaporation chamber 408 is evaporated by an irradiated argon stream, which via an inlet port 409 with is irradiated with an inner diameter of 6.0 mm. The gaseous phosphorus / argon stream enters the reactor chamber via a nozzle 410. The nozzle 410 has an opening of 4.0 mm. The evaporation chamber 408 is housed in a resistance heating furnace 411.

A gaseous mixture of potassium and argon is metered into the reactor chamber 401 via a feed nozzle 412 abandoned an inner diameter of 6.0 mm. Pure argon, which serves as the carrier gas for the potassium / argon stream, passes over the nozzle 413, which has an inner diameter of 6.0 mm, into the system. Both the potassium / argon stream and the pure argon stream enter the inlet port 414 Reactor chamber 401. The potassium / argon line 412 and the the pure argon line 413 are in an electrical one. Resistance furnace 415 housed.

The substrate 416 is held on the thermal source 402. The temperature of the substrate 416 is measured with the aid of a thermocouple 417 measured, which is arranged directly below the substrate 416 on the thermal source 40 2.

The ovens 406, 411 and 415 are separated during operation regulated to the appropriate temperatures. The gaseous reactant streams arrive at inlet ports 410 and 414 into the reactor chamber. The exhaust gas mixture leaves the reactor chamber via the ventilation nozzle 404. The product layers, which are produced in the reactor deposit on the substrate 416.

The substrates are maintained at Piner temperature in the range 310-350 ⁰ C. This temperature is maintained with an accuracy in the range of + _ 2 ^° C.

For a typical run, 1.24 g of white phosphorus and 0.13 g of potassium in the reactor in the course of 2 h to be abandoned. The total argon flow is adjusted to a volume flow of 250 ml / min.

A number of experiments were carried out in which phosphorus / argon and potassium / argon were added to the reactor at the same time. The phosphorus / argon flow is kept at a temperature of approximately 290 ^° C., while the potassium / argon flow is ^{adjusted to approximately 410 °} C. The calculated molar atomic ratio of the reactants in the reactor is adjusted so that P / K is approximately is equal to 15. The reactor is kept at a temperature of 300 to 310 ^° C. as a whole. In a typical experiment, the liquid phosphorus is fed in at a rate of 0.34 mg / h.

Amorphous KP - ^ layers are produced using nickel-deposited glass substrates. _{The KP 15} layers obtained under these conditions are approximately 0.3 mm thick.

With a test run lasting 1 hour, a thin layer is obtained, for which the nominal composition KP _{15 is} confirmed. The thickness of the layer depends on the arrangement and position of the substrate in the reactor. The scanning electron microscope is before examination shows that the layers are extremely homogeneous.

Purification of the phosphorus:

50 g of "99.95% pure" phosphorus is 75 d a temperature

BATH

profile exposed in the range of 450-300 ^{0 C.} After this relatively long residence time, 21% of the fed material remains in the feed and 60% of the feed is retained as massive amorphous precipitates.

Analyzes carried out on the input material showed that the phosphorus is not even 99.90% pure, but rather in the range of a purity of 99.80%, this phosphorus with aluminum, calcium, Iron, magnesium, sodium and silicon as the main impurities, all in an amount greater than 0.01% by weight, some were even present in concentrations greater than 0.05% by weight. This material has a purchase price of around US $ 220 per kq. In comparison, one sold with a purity level of "99%" only Phosphorus has a purchase price of only US $ 37.5 per kg.

In Table XX are the results of the flame emission spectroscopy on three substances that have been purified according to the method described at the beginning are.

Atomergic Table XX material by means of FES * "99.95" Contamination levels B. material element 0.03-0.3% material 20-200 C. 3-60 A. 2-20 Al 30-600 0.02-0.2% 3-30 Ba "4-4 40-400 *1 <2 Approx 40-400 6-60 4-40 <1 Cu , 6-6 20-200 <1 Fe 0.01-oli 0.03-0 * 3% 3-30 Pb β-60 3-30 <2 <1 Mg 6-SUN Ma 3-30 0.4-41 .6-6 30-300 Ni Q _s Q4-0 <. 4% 3-30 0.02-0.2% 4 20 N / A 6-60 MC 3-30 Si 1-10 Oa3-31 Sn MC Ti 1-10 V 0.6-6

* Flame emission spectroscopy; all values in ppm, unless otherwise stated

0.1% = 1000 ppm < MC = main component, measured at- ^ 1% ■

The material A is a residue with a dark brown color, which accrued in the entire charging zone and could not be transported via the vapor phase. The material B is obtained in the form of solid pieces of material which are light in color and cannot be evaporated, mainly because its position in the charging zone is such that a temperature of slightly less than 405 ^° C. prevails there. Material C is an amorphous piece of substance that forms in the cold zone.

It can be seen that the majority of the impurities remain in material A. It is considerably more concentrated there Shape before. The high levels of impurities leave a significant decrease in the vapor pressure of the phosphorus expect at given temperature. So the level of contamination of the material is reflected quite well in the initial one Steam pressure values of the feed. The piece of material C is an extremely pure material with traces of sodium, which are observed as the main impurity .. Taking into account of the sum of all impurities at their maximum concentration, the purified material obtained in this way has C. a degree of purity of 99.97% in the worst case. This material is comparable to a material that is used in the It is sold commercially as 99.999% phosphorus and has a price of US $ 1,800 per kg.

These results clearly show that the method of the invention for the purification of red phosphorus works extremely well well suited.

The use of phosphorus substances as flame retardants is known. Due to the high stability of the alkali metals containing phosphorus-rich substances, which are described in the present description, are recommended the substances described here for this purpose.

Fibrous and platelet-shaped modifications of the material described here, in particular, for example, the fibrous KP _1ς and KP with χ much larger than 15, the platelet-shaped monoclinic phosphorus metals, the twisted tubes made of phosphorus and the star-shaped crystals shown in Figures 44 and 45, All in all, they are promising reinforcing fillers and additives for plastics and glass. In particular, the twisted columnar fibers and the star-shaped fibers should be particularly valuable for this purpose, since, due to their geometric shape, they will bond particularly well with the matrix of a composite material. The feature of being able to act as a flame retardant should be particularly effective in such composite materials.

As already discussed at the beginning, many of the in the present Description disclosed substances highly stable amorphous coatings with particularly good adhesion to glass substrates and metal substrates. The amorphous MP .. j films are particularly stable and exhibit unusually good adhesion to metal and glass. They can be used as anti-corrosion coatings on metals and for the purpose of optical coating on glass.

A coating on an optical intended for the IR range Component, for example on a germanium crystal, with a coating thickness of 100 nm forms one in the IR range permeable window that is also opaque in the visible area. Such coatings when in appropriate Way with other coating materials different optical indices are used, can be used for the production of anti-reflective coatings on IR optics.

The applicant's tests show that the MP material with good adhesion to steel, aluminum and molybdenum in

BATH ORIGINAL

Form of adherent thin films can be deposited. These films are ductile, non-porous, polymeric and not brittle.

The materials disclosed in the above description are therefore ideally suited, in the form of coatings and thin films to be used.

The description thus discloses a completely new class of semiconductor materials with a high phosphorus content. These Semiconductor materials contain covalently bound chains Atoms, these chains forming covalent bonds forming the primary electrical conduction path in the material. the Atoms linked to form chains form columns parallel to each other as the predominant short-range order feature. The atoms in these chains are preferably trivalent with bond angles that allow the formation of tubular, spiral or Allow hollow channel-like columns. The pillars can be paired by atoms of one or more different elements or be joined together in larger numbers to form chained columns.

In the present description, in particular, phosphorus-rich semiconductor materials of this class and materials which, in addition to phosphorus, also contain other penteles. These materials include polyphosphides rich in phosphorus Formula MP with χ in the range from 7 to 15 and completely new materials for which χ is much greater than 15, namely materials that can be called pure phosphorus for all practical purposes.

These materials are characterized in that they contain groups of seven or more atoms that are pentagonals Hollow columns are chained together. They are also to be marked in such a way that they correspond to the formula MP,

where χ is greater than 6. They are further characterized in that they contain phosphorus in a molar ratio of phosphorus to any other type of atom, in a ratio of greater than 6. The phosphorus-rich substances according to the invention can be further characterized in that practically all short-range orders have phosphorus atoms which are linked by multiple covalent PP bonds, which are organized in layers of parallel pentagonal hollow columns. The phosphorus-rich substances according to the invention can also be characterized as polyphosphides which contain alkali metal atoms included, the number of successive covalent phosphorus-phosphorus bonds being sufficiently greater than the number of bonds not to be characterized as phosphorus-phosphorus bonds in the material classified as a semiconductor material. The substances can furthermore be characterized in that they have an atomic structure of at least seven covalently linked phosphorus atoms, each of which is linked to an alkali metal atom that connects the phosphorus structure of one assembly to the phosphorus structure of its own other assembly in an electrically conductive manner. These substances can also be characterized as polyphoaphids of the formula MP, in which M is an alkali metal and χ is at least equal to 7,

These materials can still be characterized by a band gap greater than 1 eV. The band gaps are usually at 1.4 to 2.2 eV, substances have also been disclosed which have a band gap in the range of approximately 1.8 eV. The substances also show a photoconductivity ratio greater than 5, in particular a photoconductivity ratio in the range from 100 to 10,000.

All these substances are further characterized by predominantly trivalent atomic units, by homoatomic units Bonds formed by the predominant types of atoms, due to the covalent nature of these bonds, due to dip

BATH ORIGINAL

Coordination number of the material, which is slightly less than 3, due to the polymeric nature of the material, due to the formation in the presence of alkali metals or metals that can simulate the bonding of alkali metals with the predominant types of atoms, are characterized by the crystalline form, their pentagonally parallel arranged hollow columns, which are either all arranged parallel to one another as a whole, as in the KP ₁ , - substances, or in pairs are arranged in parallel in intersecting layers, as in monoclinic phosphorus, or all of them are all twisted in parallel in twisted columns and twisted fibers as in the phosphor forms, are characterized by their ability to form amorphous layers and pieces which retain the electronic data of the crystals and are finally characterized by their manufacturing processes and by numerous other qualities which have been set out in detail in the preceding description.

The amorphous materials also retain the electronic properties and electronic quality of KP ₁₁ . with the pentagonal hollow column structure, which is generally aligned parallel to one another, and, at least theoretically, by the fact that this structure is also retained in the short-range region in the amorphous material. However, this statement is not intended to link the disclosed practical value of the invention to a theoretical explanation. This also applies in particular to the claims that are based on the technical content and should not lose their validity due to later improved scientific knowledge.

The specification further discloses barrier elements, photoconductive devices, photoresistive elements, photoelectric Elements and phosphors that can be made from the disclosed materials.

It was further disclosed how the specific electrical Resistance of the materials can be reduced by metering, in particular and preferably by nickel, Chromium and iron, it being theoretically obvious that doping can be carried out in the same way with all atoms and groups of atoms, the occupied outer d orbitals or f orbitals and at the same time an acceptable one Have atomic radius, can carry out.

The specific electrical resistance can also be reduced by doping with arsenic, which also results the conclusion can be drawn that practically all elements of the 5th main group of the periodic table of the elements are the will have the same effect.

In addition, barrier structures discloses having a rear contact made of nickel from which nickel diffuses into the coating and which use copper, aluminum, magnesium, nickel, gold, silver and titanium as contact metal as the upper cover contact.

Furthermore, new forms of phosphorus are disclosed which have short-range orders which are essentially parallel to one another as a whole aligned pentagonal hollow columns, twisted phosphor phases and monoclinic phosphor crystals. These new forms of phosphorus were produced by precipitation from the vapor phase. The shapes with parallel pentagonal columns and the monoclinic shapes imperatively require the present of alkali metal during precipitation.

Furthermore, the above description discloses both amorphous and polycrystalline layers of MP ₁₅ , where M stands for an alkali metal. The most varied of semiconductor components made of the materials with pentagonal hollow columns aligned parallel to one another were disclosed as structural features, including chips made of MP with much larger than 15, including new phosphor forms, including thin amorphous layers of KP ₁₅ and thin amorphous sheets cht-nn from KP.

BATH ORIGINAL

Processes for the production of metal polyphosphides have been disclosed and of two new forms of phosphorus by temperature-controlled evaporation from an evaporation source.

Processes for the production of high purity are also disclosed Phosphorus materials by two-source vapor phase transport.

A method for producing high-purity phosphorus is also disclosed.

Finally, the manufacture of crystal lines and amorphous forms of MP, where x can assume values in the range from 7 to 15, by solid-state reaction.

Processes for producing the phosphorus substances are also disclosed through chemical reaction from the vapor phase and precipitation, through extremely rapid evaporation of the feed substance and by precipitation from a controlled flow of molecules.

The industrial applications of semiconductor materials and semiconductor components, which are described and disclosed in the context of the invention encompass practically the entire range of Semiconductor applications. The crystalline materials can also as reinforcement fibers and reinforcement plates for reinforcing filling of plastics, glass and other materials to serve. The materials according to the present invention can be used for coating metals, glass and other materials to serve. The coatings can protect the substrates from fire, oxidation or chemical attack. The coatings Can be used as a window material for the purpose of IR permeability are used, such windows at the same time absorb light in the visible range. The materials can together with other materials to produce anti-reflection: coatings are used on optics that are suitable for the area of application are determined in the IR area. The materials can continue to be used

be used as flame retardant fillers and coatings. The monoclinic phosphor can be used as an optical rotating crystal (rotator).

It is obvious that the invention in the above Problems solved easily on the basis of the teachings disclosed by changes in the form described Implementation of the procedures, the processes and the change in the dimensions of the objects - systems and products solved can be without d ^. «arch the scope of the invention üu leaving. It is therefore emphasized once again at this point, All of the foregoing description is to be regarded as exemplary, not restrictive.

It is also pointed out that in parlance the present description "crystalline" always means "monocrystalline" and a polycrystalline material as "polycrystalline" unless expressly stated otherwise. Amorphous material denotes in contrast to monocrystalline and polycrystalline material a material that according to the criteria of the powder X-ray diffraction diagrams as "amorphous" is. Any reference to the Periodic Table of the Elements is binding on the table inside the front Cover of the 60th edition of the "Handbook of Chemistry and Physics" is reproduced (CRC Press Inc., Boca Raton, Florida). The alkali metals are referred to there as here as group 1a and the penteles there as here as group 5a. All specified Areas include the limit values.

Semiconductor components in the sense of the description are devices or apparatuses that use semiconductor material. Special semiconductor components are also xerographic surfaces and Phosphors, regardless of how they are excited, and are ultimately also photoconductors, photocells, Sperryehichtelentente, Tx ~ ansistören, integrated circuits and the like

BATH ORIGINAL

-yso -

Elements.

Furthermore, it should be noted that in the following claims all superordinate and generalizing as well as all
specific aspects of the disclosed invention are intended to be included. This also and especially applies to the generalizing concept formation.

It is particularly important to ensure that in the formulation of the Claims components or substances are cited in the singular, but readily compatible mixtures of the individual Components or parts, insofar as the meaning permits, are expressly to be classified as included.

eerseite

Claims (1)

Patent to sayings 2. A new form of solid phosphor material in which the
Phosphorus atoms are linked together by several covalent phosphorus-phosphorus bonds, which form essentially pentagonal tubular arrangements of bound phosphorus atoms, the short-range order being defined at least essentially over the entire phosphorus by the fact that the tubular arrangements with their axes predominantly essentially parallel to one another are aligned. 3. A solid stable material of the formula MP, in which M
at least one alkali metal and P mainly phosphorus BERGSTRASSE 4β '| ι · O-eOSBMÜNCHEN-GAUTING TECEPHON: (O ββ) 8BO9O3O · TELEX: 68177. tsar d are, but P is also one or more penteles and X is greater than 15. 4. A phosphorus-rich material obtained as the product of precipitation at least one of the vapor phase transport from separately heated sources of phosphorus vapor and the vapor Metal. 5. High phosphorus polyphosphide film material obtained by chemical reaction and vapor deposition (CVD). 6. Phosphorus-rich polyphosphide film material obtained by rapid evaporation of the starting substance. 7. Semiconductor component made from a material which consists essentially entirely of atoms, the make up by far the greatest majority of all atoms in the material and only three homoatomic covalent ones Bindings. 8. Semiconductor component made from a material that has a short-range order at least essentially throughout having, which is characterized by groups of 7 or more atoms, which are! covalently connected to one another are that they form essentially pentagonal hollow columns. 9. Semiconductor element made of a material which essentially continuously has a short-range region which is defined by polyphosphide groups of the formula MP where M is a metal and χ is greater than 6. 10. Semiconductor element, consisting essentially continuously of a material with a short-range order that defines is through atoms that are linked together by several covalent atom-atom bonds and layers of pentagonal hollow columns form, these hollow columns within each layer is essentially parallel to one another are aligned. ' 11. Semiconductor element consisting of an inorganic one Material which, as its predominant short-range order, is concatenated essentially over its entire extent having homoatomic covalently bonded atoms, essentially all of these covalent bonds of the Materials are involved in the concatenation of the atoms and the covalent bonds establish the predominant electrical conduction pathways in the material, and wherein the material has a band gap substantially in the range of 1.4 to 2.2 eV. 12. A semiconductor element containing an inorganic material as its predominant short-range order essentially above its entire extent has chains of homoatomic covalently bonded atoms, essentially all of these covalent bonds of the material are involved in the chaining of the atoms and the covalent bonds are the predominant ones forming electrical conduction paths in the material and wherein the material has a photoconductivity ratio substantially within the range of 100 has up to 10,000. 13. Semiconductor element containing a phosphorus-rich polyphosphide material, condenses from the vapor phase in the presence of an alkali metal. 14. Device for vapor phase transport, characterized by a single heat source for two vapor species and one .: ..: .. \ Λ:. \ 3247889 elongated precipitation zone, which on essentially is kept constant temperature. 15. Device for the vapor phase transport, marked by a single source for two vapor species present in a first zone is heated and at least two further zones, which are in communication with this zone, and on at least two other temperatures are maintained. 16. Device for vapor phase transport, marked by at least two separate heated sources for at least two different vapor species. 17. Device for chemical reaction in the vapor phase and subsequent precipitation, marked by: Ά) a heated chamber; B) a substrate in the chamber; C) means for evacuating gas from this chamber; and D) a gas flow of a first vapor component which is enveloped in a gas flow in the chamber entry. 18. Process for chemical reaction and for precipitation from the vapor phase of phosphorus-rich polyphosphide material, marked by separate gas streams of vaporized phosphorus and a vaporized alkali metal over a condensation substrate. 19. device for rapid evaporation, characterized by a heated receptacle and means for flowing of material through this receptacle. 20 «Process for rapid evaporation, .. gekennzeichn et that a material for the purpose of its evaporation by a heated receptacle is flowed. 21. Material made by ball milling together at least one alkali metal with at least one pentel. 22. A process for the production of polyphosphide material of the formal MP, where M is at least one metal and P mostly Phosphorus means, but can also include at least one pentel, by vapor phase transport, wherein two heated separate sources for phosphorus and at least one metal and a separate precipitation zone are provided which has a substantially constant temperature over a larger surface area. 23. A method for producing essentially pure phosphorus by depositing the phosphorus after vapor phase transport on a substrate made of a metal poly- phosphidt. ■ / Method of making metal polyphosphide material, characterized in that at least one metal and phosphorus are in one zone Controlled temperature are heated and from the steam produced in this way, the metal phosphide in a second zone of controlled temperature, the one substantially constant temperature over a larger one Has surface area is deposited. 25. Process for the preparation of high phosphorus polyphosphide material of the formula MP, in which M is at least one metal and P is phosphorus, characterized , that M and P are heated together and then be cooled to room temperature. 26. Crystalline twisted phosphor fibers. 27. Crystalline polyphosphide material in the form of star-shaped rods. 28. Monoclinic phosphor material condensed from the vapor phase in the presence of a significant amount of alkali metal vapor. 29. Highly pure phosphorus, condensed from the vapor phase at a temperature essentially in the range from 500 to 550 ^° C. 30. Material containing a monoclinic phosphor crystal with a largest dimension of substantially larger than 0.2 mm. 31. Material containing a monoclinic phosphor crystal with a smallest dimension of substantially larger than 0.05 mm. 32. Optical rotator made from monoclinic phosphor material. 33. A process for the production of high-purity phosphor material, characterized in that that phosphorus evaporates in a sealed ampoule and is condensed at a temperature which is at least ¹ T- O/ lies substantially in the range 500-550 ⁰ C. 34. A composite material containing monoclinic phosphorus " 35. A flaran retardant material containing a high phosphorus Polyphosphide. 36. A filler containing a phosphorus-rich polyphosphide. 37. A reinforcing filler material for composite materials, containing a crystalline, phosphorus-rich polyphosphide. 38. Protective coating material containing a pentel-rich polypentel. 39. Optical coating material containing a pentel-rich polypentel. 40. Anti-reflective coating material comprising at least a layer of pentel-rich polyp ice. 41. Doping of phosphorous-rich semiconductors with other penteles. 42. Doping phosphorus-rich semiconductors with a metal that has occupied outer d-levels or f-levels. 43. A method of manufacturing a semiconductor element characterized by the following Process stages: a) Submission of a material which contains at least one of its components a polyphosphide which Contains phosphorus-phosphorus bonds and alkali contains metal atoms' bonded to the phosphorus atoms and wherein the number of consecutive covalent phosphorus-phosphorus bonds is sufficiently greater than the number of non-phosphorus-phosphorus bonds, so sufficiently larger that the material is semiconducting is; and b) Attaching to the material of means for an electrical Connection with the material for the use of the material as a semiconductor. 44. A method for producing a semiconductor element, characterized by the following procedural steps: a) Specifying a material that is at least one its components contain at least two polyphosphide units, each of which has a skeleton of at least Has seven covalently bonded phosphorus atoms, with these units at least one alkali metal atom is connected, the electrically conductive the phosphor framework one unit connects to the phosphor skeleton of the other unit, and wherein the material is a band gap which is primarily determined by the phosphorus-phosphorus bonds; and b) Attachment to this material of funds for the electrical connection with the material for use ^{1 of} the material as a semiconductor. 45. A method for producing a semiconductor element, characterized by the following procedural stages: • 'Λ- » a) Specifying a material which contains at least one of its components a polyphosphide which has the formula MP, in which M is an alkali metal and χ is the atomic ratio of P to M, where χ is at least equal to 7 and where this material has a band gap im Has a range of 1 to 3 eV;
and b) Attaching to (the material of means for electrical Connection with this material for the use of the material as a semiconductor. 46 "Material produced in the apparatus according to one of the Claims 14 to 17 or 19. 47. Material made by a method according to a of claims 18, 20, 22 to 25, 33 or 41 or 45. 48. Semiconductor element produced from a material according to one of Claims 1 to 6, 46 or 47. 49. Invention according to one of claims 1 to 13, 18, 21, 22, 24, 25, 27, 28, 30 to 40 or 43 to 48, characterized in that that the material contains a single alkali metal. 50. Invention according to one of claims 1 to 13, 18, 21, 22, 24, 25, 27, 28, 30 to 40 or 43 to 48, characterized in that the material is at least two different alkali metals contains. 51. Invention according to one of claims 4, 6, 9, 18, 21, 22, 24, 25, 35 to 37 or 43 to 50, characterized in that there are at least 7 phosphorus atoms in the material Phosphorus atoms each contain a metal atom in the material. 52. Invention according to claim 51, characterized, that 15 phosphorus atoms bonded to other phosphorus atoms are each a metal atom in the material. 53. Invention according to claim 52, characterized , that at least 500 phosphorus atoms per metal atom in the Material available. 54. Invention according to claim 53, characterized , that the material can be represented by the formula (MP ₇ ) (P _q ) k, where b: a is the atomic ratio (Pg) ^to (MP ₇ ). 55. Invention according to one of claims 1 to 13, 21, 22, 24, 25, 27, 28, 30 to 40 or 43 to 54, characterized, that the polyphosphide has the formula MP and χ is substantially equal to 15. 56. Invention according to one of Claims 1 to 13, 21, 22, -24, -25, 27, 28, 30 to 40 or 43 to 54, characterized, that the polyphosphide has the formula MP and χ greater than 14 is. 57. Invention according to one of claims 1 to 13, 21, 22, 24, 25, 27, 38, 20 to 40 or 43 to 54, characterized , that χ ranges from 7 to 15 inclusive. > 0 · 58. Invention according to a dpf claims 1 to 13, 21, 22, 24, 25, 27, 28, 30 to 40 or 43 to 57, characterized in that the metal is Li. 59. Invention according to one of claims 1 to 13, 21, 22, 24, 25, 27, 28.30 to 40 or 4 3 to 57, characterized in that the metal is Na. 60. Invention according to one of claims 1 to 13, 21, 22, 24, ? 5, 27, 28, 30 to 40 or 43 to 57, characterized in that the metal is K. 61. Invention according to one of claims 1 to 13, 21, 22, 24, 25, 27, 28, 30 to 40 or 43 to 57, characterized , that the metal is Rb. 62. Invention according to one of claims 1 to 13, 21, 22, 24, 25, 27, 28, 30 to 40 or 43 to 57, characterized in that the metal is Cs. 63. Invention according to one of claims 2, 7, 8, 10 to 12 or 43 to 48, characterized, that at least 6/7 (six-seventh) of the atoms exclusively Have 3 homoatomic bonds. 64. Invention according to claim 63, characterized in that at least 14/15 (fourteen-fifteenth) of the atoms Have 3 homoatomic bonds. ^ 12 - 65th, invention according to claim 64, characterized , that the proportion of atoms of the species that are homoatomic Wear ties much larger than 14/15 (fourteen-fifteenth) is. 66. Invention according to one of claims 2, 13, 18, 21, 22, 24, 25, 29, 33, 35 to 40 or 43 to 48, characterized , that the material in the short-range order area through a hollow columnar structure is characterized. 67. Invention according to claim 66, characterized in that the hollow column structures in the near area as a whole are generally aligned parallel to one another. 68. Invention according to one of claims 66 or 67, characterized in that that the atoms of the main component of the material are trivalent. 69. Invention according to one of claims 6 6 to 68, characterized in that that the hollow column structure is channel-like seen from the front side. 70. Invention according to one of claims 66 to 69, characterized in that that the column structure is pentagonal when viewed from one end face. 71. Invention according to one of claims 68 to 70, characterized in that the atoms are atoms of at least one pentel. LS. '.- ¹ p. 3247863 - 13 -. ■ ' 72. Invention according to one of claims 66 to 71, characterized in that the atoms are predominantly phosphorus atoms. 73. Semiconductor element according to one of claims 7, 8 or 10 to 12, characterized in that the bonds of the atoms enclose an average bond angle of greater than 98 °. 74. Semiconductor element according to Claim 73, characterized in that that the bond angle is in the range of 87 ° to 109 °. 75. Semiconductor element according to one of claims 11 or 12, · marked by additional atoms of one or more elements as atoms of the linkages, bound between two or several of these chains, 76. Semiconductor element according to claim 75, characterized in that that the additional atoms form conduction paths between the chains to which they are bound. 77. Semiconductor element according to claim 75 or 76, characterized in that that the concatenations in each short-range area are as a whole essentially parallel to one another. 78. Invention according to one of claims 1 to 13, 18, 21, 22, 24, 25, 33, 35 to 40, 43 to 48 or 65 to 77, characterized in that the material is the precipitate product of vapor phase transport from separate sources of phosphorus and an alkali metal is formed in a precipitation zone. 79. Invention according to one of claims 7, 8, 10 to 12, 43 up to 48, 63 to 65 or 71 to 77, characterized, that the essential majority of the atoms are phosphorus atoms are. 80. Invention according to one of claims 3 or 4, 5, 9, 13, 18, 22, 24, 25, 28, 30 to 32, 34 to 37, 43 to 48, 49, 53, 54, 58 to 62, 78 or 79, characterized , that the atomic ratio of phosphorus to metal is essentially 50 or greater. 81. Invention according to claim 80, characterized, that the atomic ratio is substantially 200 or greater 82. Invention according to claim 81, characterized, that the atomic ratio is substantially 1000 or more 83. Invention according to claim 82, characterized , that the amount of the metal is less than 1000 ppm. 84. Invention according to one of claims 1 to 13, 18, 22, 24, 25, 33, 43 to 53, 63 to 65 or 73 to 77, characterized, that the material has a band gap substantially within the range of 1 to 3 eV. 85 «Invention according to claim 84, characterized in that that the material has a band gap substantially within the range of 1.4 to 2.2 eV. 86 = Invention according to Claim 85, characterized in that that the material has a band gap of substantially 1.8 eV hatο " 87 «, invention according to one of claims 1 to 13, 18, 22, 24, 25, 33, 43 to 53, 63 to 65, 73 to or 84 to 86, characterized, that the material has a photoconductivity ratio in the range of 100 to 10,000. 88. Invention according to one of claims 1 to 13, 18, 22, 24, 25, 28, 29, 30, 33 or 43 to 73, characterized in that the material is a single crystal. 89ο Invention according to one of claims 1 to 13, 18, 22, 24, 25, 29, 33 or 43 to 87, characterized in that that the material is polycrystalline. 90 «invention according to one of claims 1 to 13, 18, 22, 24, 25, 29, 33 or 43 to 87, characterized in that the material is amorphous. 91. Invention according to one of claims 1 to 14, 18, 22, 24, 38 to 40, 43 to 87 _# 89 or 90, characterized in that the material is in the form of a thin layer. • ir? 16 - ■ 1 ': ■ 92. Invention according to claim 91, characterized , that the thin layer is applied to a glass substrate is. 93. Invention according to claim 91, characterized in that the thin layer is deposited on a metal substrate is. 94. Semiconductor element according to one of claims 7 to 13, 46, 47 or 73 to 77, characterized by a blocking transition. 95. Semiconductor element according to Claim 94, characterized in that that the barrier junction is a metal of the group copper, aluminum, magnesium, nickel, gold, silver or titanium contains. 96. Semiconductor element according to Claim 95, characterized in that that the transition metal is nickel. 97. Semiconductor element according to one of Claims 7 to 13, 46, 47, 73 to 77 or 94 to 96, characterized in that the metal has atoms of a different pentel is endowed. 98. Semiconductor element according to Claim 97, characterized in that that the Pentel is arsenic. 99. Semiconductor element according to one of claims 7 to 13, 46, 48, 73 to 77 or 94 to 98, characterized in that the material is doped by diffusing in a metal which has outer occupied f-levels or d-levels . 100. Semiconductor element according to claim 99, characterized in that that the dopant is nickel, iron and / or chromium 101. Semiconductor element according to one of claims 7 to 13, 46, 47, 73 to 87 or 94 to 100, characterized by a contact metal which is copper, aluminum, magnesium, nickel, gold and / or titanium. 102.Doping according to claim 41, characterized in that the penteles are arsenic, antimony and / or bismuth. 103.Doping according to claim 102, characterized in that the pentel is arsenic. ο doping according to one of claims 41, 102 or 103, characterized in that the ratio of the other penteles to phosphorus is less than 50%. 105. Doping according to Claim 104, characterized in that that the ratio is less than 10%. al 18 - 106.Doping according to claim 42, characterized in that the metal is iron, nickel and / or chromium. 107. Invention according to one of claims 1 to 13, 18, 21, 22, 24, 25, 27, 28, 30 to 40 or 46 to 48, thus marked, that the material contains an alkali metal. 108. Invention according to claim 107, characterized , that at least 7 phosphorus atoms to other phosphorus atoms are bound, one metal atom each in the material. 109. Invention according to claim 108, characterized , that at least 15 phosphorus atoms to other phosphorus atoms are bound, one metal atom each in the material. _11O invention according to claim 109, characterized in that that the ratio of the phosphorus atoms to the metal atoms In the material is at least 500: 1. 111. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized in that the metal is lithium. 112. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized in that the metal is sodium. 113. invention for a d _ti claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110 characterized in that the metal is potassium. 114. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized in that the metal is rubidium » 115. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, thereby marked c h η e t, that the metal is cesium. 116. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized, that the material is LiP and χ is at least 7. 117. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized in that the material is NaP and χ is at least 7. 118. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized , that the material is KP and χ is at least 7. 119. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized, that the material is RbP and χ is at least equal to 7. '* * ... 20 - * 'ti ¹ 120. Invention according to one of claims 63 to 65, 73 to 77, 84 to 87, 94 to 101 or 107 to 110, characterized in that that the material is CsP and χ is at least 7. 121. Invention according to one of claims 84 to 87, 94 to or 106 to 120, characterized in that the material has a band gap substantially substantially Range from 1 to 3 eV. 122. Invention according to claim 121, characterized in that the material has a band gap substantially substantially Range from 1.4 to 2.2 eV. 123. Invention according to claim 122, characterized in that the material has a band gap of substantially 1.8 eV has. 124. Invention according to one of claims 84 to 87, 94 to 101 or 106 to 120, characterized in that the material has a photoconductivity ratio in the range from 100 to 10,000. 125. Highly pure phosphorus according to claim 29, characterized in that that the high purity phosphorus is condensed in the presence of a significant amount of alkali metal vapor. 126. High purity phosphorus as claimed in any of claims 29 or 125, is condensed at a temperature substantially equal to 539 ⁰ C. 127. Monoclinic phosphor according to one of claim 30 or 31, condensed from the vapor phase in the presence of a significant amount of an alkali metal vapor. 128 »The monoclinic phosphor of claim 127 condensed from the vapor phase at a temperature substantially within the range of from 500 to 550 ^° C, inclusive. ο Monoclinic phosphor according to claim 127, condensed at a temperature essentially Iron 539 ⁰ C. 130. The method according to claim 20, characterized in that the flowing material contains phosphorus » 131. The method according to one of claims 20 or 130, characterized in that the flowing material contains an alkali metal 132. Material made by the method of a of claims 20, 22, 33, 130 or 131. 133. Material according to Claim-132 in the form of a thin layer. 134. Material according to claim 133, characterized by the fact that the material is polycrystalline. 135 "Material according to claim 133, characterized , that the material is amorphous » 136. Monoclinic phosphorus according to one of claims 28, 30, 31 or 127 to 129, characterized , that the phosphorus contains alkali metal, essentially within a range of 50 to 2,000 137. Monoclinic phosphor according to one of claims 28, 30, 31, 127 to 129 or 136 with a platelet-shaped habit. 138. Monoclinic phosphor according to one of claims 28, 30, 31, 127 to 129, 136 or 137 with a truncated pyramid Habitus. 139. Monoclinic phosphor according to one of claims 28, 33, 127 to 129 or 136 to 138, characterized, that the steam is at a temperature in the range of 546 to 564 ⁰ C is formed. 140. Invention according to one of claims 28, 127, 136 or 138, characterized in that the alkali metal is sodium. 141. Invention according to one of claims 28, 127, 136 or 137, characterized in that the alkali metal is potassium. 142. Invention according to one of claims 28, 127, 136 or 138, characterized , that the alkali metal is rubidium. 143. Invention according to one of claims 28, 127, 136 or 137, characterized, that the alkali metal is cesium. 144. Phosphorus according to claim 26, condensed from the vapor phase at substantially 509 ^° C. 145. Polyphosphide according to claim 27, condensed from the vapor phase at a temperature less than 500 ^° C. 146. The polyphosphide of claim 145 condensed at substantially 462nd. ⁰ C. 147. Coating according to one of claims 38 to 40 on a glass substrate. 148. Coating according to one of claims 38 to 40 on one Metal substrate. 149. Coating according to one of claims 38 to 40, characterized in that the pentel is phosphorus. 150. Coating according to one of claims 38 to 40, characterized, that the coating is amorphous. 151. Reinforcement material for composites _t containing a crystalline MP, where M is an alkali metal, P is phosphorus and χ is equal to or greater than 7. 152. Reinforcing material for composite materials containing crystalline MP ₁₅ , where M is an alkali metal and P is phosphorus. 153. Reinforcement material for composite materials, containing a crystalline MP, where M is an alkali metal or is at least one other metal that simulates the bond of an alkali metal, P is phosphorus and χ is equal to or greater than 7. 154. Reinforcing material for a composite material containing crystalline MP ₁₅ , where M is an alkali metal or at least one metal that simulates the bonding of an alkali metal, and P is phosphorus. 155. Material according to one of claims 35 to 37 or 151 to 154, characterized in that the material is embedded in glass. 156. Material according to one of claims 35 to 37 or 151 to 154, characterized, that the material in a plastic or in a Plastic molding compound is embedded.