DE1521834B2 - METHOD FOR MANUFACTURING LAYERED SEMICONDUCTOR CRYSTAL ELEMENTS BY ETCHING - Google Patents

Description

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The invention relates to a method of manufacturing composite semiconductor material on the etched layered semiconductor crystal elements such. B. surface. With this procedure it is Transistors or the like, but not possible using etching, the semiconductor surface in this way to carefully and slowly etch semiconductor crystal surfaces in a reaction process, as is the case with the Herkammer by means of a flowing gas mixture under 5 position complicated semiconductor components required heating of the element on increased, but under- borrowed. It is also known (German patent half a melting point lying temperature and writing 966 879), for the removal of semiconductor subsequent treatment in the same material hydrogen halide alone as an etchant Reaction chamber. use. However, the known method has the

In the manufacture of semiconductor components ίο the disadvantage that the etching speed does not de-

layers on semiconductor crystal wafers can be controlled from finely finished.

Semiconductor material or of dielectric material The object of the invention is therefore to be deposited. So that the properties of the finished creation of a method for the formation of layer components are not impaired by undesired disturbances of the th on semiconductor crystal elements with a previous structure, the surface 15 must be etching of the wafer surface, in which the etching in the semiconductor wafer before the layer is deposited. In contrast to known methods, to be flawlessly as smooth and clean as possible. For this purpose, a clean and smooth surface leads and the Mög etching process is known, in which a vaporous possibility of the deposition of impurities between the etchant itself on the semiconductor element, whose etching and the application of the desired temperature below the condensation temperature ao layer is prevented. In particular, the vapor should practically lie when the liquid precipitates. Since no etching residues remain on the platelets, but the etchant does not remain on the platelets indefinitely. Finally, the method according to the invention should remain on the semiconductor platelets, it must be removed after the use of silicon oxide films as a cover etching process. For this purpose, either to prevent spitaxial growth of the halide, the etchant itself is allowed to sweep over the platelets at high speed on certain parts of the surface, but this results in the formation of previously unproducible semiconductor components and a high consumption of etchant; or you can use elements to enable. The method is also intended to allow an additional stream of pressurized gas, which blows the etching using tubular furnaces and similar furnaces for the medium from the platelets, or it is intended to enable the deposition of epitaxial layers,
corrosive platelets on a turntable, so that the 30 According to the invention, this object is thereby released liquid etchant by centrifugal force from the platelets that one is thrown off as a gas mixture and hydrogen chloride. The disadvantage of this known hydrogen in a defined controllable ratio verVerfahren is mainly that it turns and then the element in the reacfluid etchant can only be removed completely from the tion chamber with difficulty Metal oxide cover layer or that is subject to solid-state diffusion much faster at scratches or deeper,
lying damage points than on the smooth paths of the high temperature of the semiconductor wafer surface parts, so that it condenses in these damaged surfaces while the vaporous etchant remains as a residue and the etching process in not, so that the etching process is effected without undesirably continuing This damage is formed by etching residues which, in addition to the aforementioned conditions, are more likely to be increased than compensated for. Would cause damage. In addition, there are no such structural disturbances, inter alia, additional aids for the removal are undesirable because the diffusion etchants are present on them. The method according to the invention is therefore different from the other places, so it is much simpler than known methods and results in the evenness in the formation of the surfaces,
different semiconductor zones is not guaranteed. Preferably addition Germa-be metal oxide, in the treatment of the optionally platelet temperature niumplättchen at least silicon or germanium platelets deposited over 700 ⁰ C, for silicon wafer on, at least, non-uniform, so that for example in the 85O ° C. On the one hand, there is no risk of the formation of integrated capacitors, deviating condensation of the etchant, on the other hand, the desired values are still determined. Likewise, no melting of the semiconductor wafers. A gas mixture of vaporous chlorine values appears as etching deviations from the desired resistance means, if resistance materials based on non-hydrogen and hydrogen gas are used, which are deposited on completely clean surfaces. When flowing over the platelets.

Depositing Epitaxial Semiconductor Material Layers on 55 To form an epitaxial layer on top of the

not entirely flawless surfaces arise after the etching surface can be a mixture of

Crystal structure disturbances, which the semiconductor gas and germanium tetrachloride or SiIi-

keep affecting in an uncontrollable manner, so that zium tetrachloride flow over the heated platelets

do not allow the desired parameters of the component.

be enough. Even with well-cleaned semiconductor material, the crystal platelets should only be etched selectively If atmospheric dust particles can easily form, they can be on their surface before the etching process or a surface that has crumbled off from the treatment furnace with an adhering, opposite to chlorine water particles settle on the semiconductor wafer and provide a fabric-resistant cover coating in Give cause for faults. which openings are formed for the etching.

It is known (Austrian patent specification 212 879) that metal oxide films should be formed on the surface

using a halide of the semiconductor, the platelets can be made of a metal halide

materials with hydrogen as the reactant must first be exposed to low vapor. For training one

to etch and then by changing the gas to oxide film you can create a mixture of a metal

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halide vapor and water vapor over the platelets. Further details can be found in the following

let flow. If, for example, the metal halide description based on the representations of

Niddampf is silicon tetrachloride, forms on the embodiments of the invention. It shows

Crystal elements from a silicon oxide film. For education Fi g. 1 is a schematic representation of both

one to cover the surface of the semiconductor material- 5 for gas etching as for inducing epitaxial

the oxide layer, the platelets after etching growth suitable device,

heated to an appropriate temperature. Should this F i g. 2 is a perspective view of one with

Layer be a silicon oxide layer, this silicon oxide-coated platelet made of semiconductor

by heating the platelets after etching on material with a rectangular opening in the silicon

over 800 ⁰ C and painting over the platelets with io oxide,

Form water vapor. F i g. 3 shows a section through the in FIG. 2 shown

After the selective etching it can be seen on the platelets along the line 3-3,

etched surface areas a semiconductor material F i g. 4 make the same cut with one in the material

■ deposit epitaxially in such a way that between the pre-etched recess,

initial semiconductor material of the wafer or 15 F i g. 5 the same cut after the indentation

Carrier and the epitaxially grown material was filled with epitaxially grown substance,

a pn junction is created. F i g. 6 further process steps for production

Special semiconductor components can be achieved, a transistor from the structure according to FIG. 5,

if, for example, in the semiconductor crystal flakes F i g. 7 process steps of a process for elec-

Depressions are etched, which are then isolated by 20 tric isolation of certain zones on a plate

epitaxially grown semiconductor material filled with semiconductor material,

will. F i g. 8 the use of gas etching in the manufacture

Particularly good surfaces and deposited layers of mesa transistors,

th result if one considers the semiconductor crystals F i g. 9 the silicon oxide coating of a chlorine

ments as platelets on a flat surface of the exposed mesa structure,

arranges and this inclined at a small angle F i g. 10 the in F i g. 1 device shown der-

introduces into the reaction chamber so that the plate is modified so that silicon oxide films are deposited on silicon

which can be formed through the reaction chamber,

flowing gas are opposite. Here, FIG. 11 shows the device shown in FIG If the reaction gas strokes all the platelets at the same time, modified in such a way that different types of oxide are formed, so that the reaction process is also formed on velvet films on silicon and germanium borrowed platelets in the same treatment time very can, and

occurs uniformly, while otherwise the reaction F i g. 12 the in F i g. 1 shown device such

modified faster on the platelets facing the gas flow, so that they also lead to solid-state diffusion

can be done. 35 can be used.

For the training of do- The in F i g. 1 system shown schematically, the crystal elements can after the etching of germanium and silicon platelets a flowing, the desired doping material with hydrogen chloride gas and the formation of epitaxial rial containing gas and at the same time a high, layers on these platelets. In a temperature which is normally below its melting point, however, the reaction chamber 1 made of quartz is to be exposed. Germanium or silicon platelets on a quartz plate 3, which is usually made of quartz plate 3, which are placed on a support 4 made of graphite or standing reaction chambers, lightly Ger molybdenum rests on the walls of the quartz. The base 4 is heated by high manium or silicon deposits, the frequency at times via an induction coil 5; thereby crumble off and the germanium or silicon material will fall onto the semiconductor wafers initially found in the reaction chamber, where it is indirectly heated and warmed up as soon as there are points of failure. When used as an etchant it is hot, directly by induction,
a gas containing hydrogen chloride, the When etching, gaseous dry water tendency to form crystallization nuclei flows out of the storage container 7 through the inlet hood 8, which can be removed from this and a growth of germs taking place thereon, into the reaction chamber 1. nium and - to a lesser extent - also silicon by means of the valves 17 and 18 and the flow greatly reduced. Therefore, the quartz furnace remains at knife 11 and 12, the flow rate of this treatment is clean inside, so that the above-mentioned of hydrogen and added hydrogen chloride undesirable phenomena do not occur. from the container 6 and the proportion of these

Controlled on thin silicon oxide films on germanium or 55 both gases to each other. Can be used for cleaning

When applied silicon, the treatment allows the system by opening the nitrogen valve 14

Turning silicon oxide films for a few minutes with nitrogen from the source 13 as a protective or protective layer

covering agent against epitaxial growth. By pre-flushing.

see openings in the film prior to gas etching. The hydrogen chloride container 6 and the hydrogen can the epitaxial growth on the open fields 60 and nitrogen tanks 7 and 13 are barricaded while on the silicon faucets 10, 9 and 14, so that the supply of these dioxide does not deposit any silicon or germanium. Gases without changing the setting of the control

Since the pilot valves 17 and 18 in the silicon oxide film can be blocked. By the

Opened supports seen in the area of this valve 15 are used for epitaxial growth.

Openings etched deep and then cut off again with epitaxially 65 the control materials and supplies 16,

Washable material can be refilled, is one when it is not needed,

good three-dimensional geometric monitoring of the After cleaning, devices are used to etch

given epitaxial growth. manium germanium platelets 2 in the reaction

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chamber over 700 ⁰ C, but not on the Schmalz- In the F i g. 2 to 9 are manufacturing processes

temperature of germanium, in the presence of chlorine from semiconductor devices with advantageous anwaa-

hydrogen gas heated. The temperature is increased with a mixture of bhandlungan with caloric water.

optical pyrometer measured, tending gas and masking techniques shown.

For the etching of silicon, the silicon plates are 5 F i g. 2 shows a Girmanium plate 2) with a

Chen to temperatures above 850 ° C. to below the thin silicon oxide film 21 on its upper surface. In

Heated silicon melting point. the silicon oxide film is a right; kigis window 22

The hydrogen chloride gas is incorporated by mixing, e.g. by etching out

Hydrogen gas diluted to the right degree, and dilute hydrofluoric acid, with the rest

this mixture is over that of the chlorinated water io silicon oxide by covering it with a opposite

fabric-etched platelets. The hydrofluoric acid resistant material that forms is valued

volatile products will be released from the gas flow through it.

the reaction chamber to the combustion opening 79 out- F i g. 3 shows a section through what is still being driven. After the etching, the platelets can be made from unetched platelets 29 along the line 3-3. Can be removed in the reaction chamber; 15 Fig. 4 is a recess 23 in the germanium 2D, however, it is etched as a carrier material for epitaxial growth. For this purpose, the platelets are heated to over 703 ° C., so they normally remain untouched in a flowing mixture of hydrogen chloride and hydrogen atmosphere in the reaction chamber. gas and hydrogen gas. In Fig. 5 is the in Epitaxial layers are drawn out on the platelets 2. F i g. The recess 23 shown in FIG. 4 is formed with epitaxially grown by heating the platelets and filling a 20 nm germanium 24. Since the silicon oxide was exposed to a gaseous mixture of hydrogen and a gas containing hydrogen chloride in the hot compound of the corresponding semiconductor material, no germanium z. B. silicon tetrachloride, germanium chloride or formed on the film 21. A simple epitaxial trichlorosilane, created over the exposed surfaces of the diode, when the platelet 29 flows against the opposing platelets. The temperature of the wafer is 25 sat conductivity of equiaxed substance 24 has performed for germanium at 700 and 850 ⁰ C and for silicon at Because the etching of the recess 23 and their Auff üllea Looo to 1300 ° C. The gaseous materials set with epitaxial substance 24 If you can, preferably on the exposed platelet upper surface without the platelet from the reaction chamber 1 around, with a layer being removed on these surfaces, the transition 25 of the to the tea made of monocrystalline semiconductor material of the same types of glass can be very clean be held Chen form crystalline orientation. For doping F i g. 6 shows how the in FIG. The formation of the epitaxially growing material shown in FIG. 5 can subject the gaseous substances to a further epitaxial process a hydrogen compound of the can, so that a transistor is created. Diborane and arsine. The epitaxial oxide film 21 and the epitaxially grown gerina growth and doping precursors can be formed very precisely. In stage 2, a window 27 is controlled in such a way that the contamination condenser is etched out of the silicon dioxide and the doping level is kept within narrow limits. ItiS £ uf3 is with thent containing CJilorhydrogen and also the Dbken en »are toleratedea Äcöanai. Gas «ine recess 28 in the epitaxial substance 24. One difficulty is that small amounts 40 have been etched. In stage 4, this recess is filled with new silicon or germanium, which are deposited on the walls of the epitaxial substance 29 from opposite guide reaction chambers, which have a tendency to be depressed in a way that a pnp or npnzaiblapeln and towards the platelets fall so that transistor results.

form unwanted disturbances of the lattice structure. If, however, two Dio-W'erdea quartz reaction chambers are formed in the same semiconductor substrate in the 45, 3f and 31 (level 1 of FIG. 7), objects made of quartz can be used with a high level of practical substance Insulate hydrogen-containing gas at high temperatures from one another. Such insulation "ngsausgesetzt so set t practically during epitaxla- techniques clen growth are readily ele in the production! No germanium or silicon more Irish circuits in Halbleäterträgera useful on the quartz off, and the Epitaxiaischicht 5 formed" In Stage 1 of the F i g. 7 there are two p-zones 39 and 31 on has a much better quality. a common section 32 of n-semiconductors. This quality is also formed in another way, which in turn improves one: the reaction chamber made of quartz cut the p-substance 33 of high resistance and only warms itself up very much by the induction coil represents. In stage 2 the obscure flee is the n- and p-abwenig, since quartz is a non-conductor. The deposits 55 were coated with silicon oxide 34. In stage 3 is on the walls of the chamber are therefore very low. a zone 35 of the silicon oxide between the p-Ab. In other silicon oxide forms, the same advantageous sections 3D and 31 are removed. In level 4 there is a deeper effect. Incision 36 has been etched through the η-section in the opposite of the method used earlier, the lower p-Zoue 33, iadera the material in etching away from parts of an epitaxial layer to the 60 in the manner described above, hydrogen chloride oil mixed form offers the use of a silicon has been exposed to holding gas. In stage 5, ρ SaboxidfiHms as an etching mask of germanium or silicon punch 37 in the vertex “pitactic deposited, is advantageously an extraordinarily good one, so that the pn connection below the p-type three-dimensional control option for the epistance 39 from the pn junction under the p substaoz taxial growth. The use of these films ais 65 at 31 is isolated.

Cover with gas etching and epitaxial film formation The cover with silicon oxide and the gas power, the production of novel semiconductor elements etching are also advantageous, for example, to make clean, more accurate Ätzverbmdungen such . B.

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Collector coatings for mesa transistors. F i g. 8 shows the desired temperature being heated, and the chlorine

the individual production stages of such collector hydrogen gas initiated. A suitable temperature

Transitions. Stage 1 is based on a part of a Ger- for silicon is 1200 ⁰ C, for germanium 900 ⁰ C. That

manium or silicon plate. Stage 2 shows a hydrogen chloride gas is fed into the reaction chamber

Plate 38 after the formation of a silicon film. 5 left to start the etching process. At the

Step e 3 shows the platelet 38 with silicon oxide 39. Etching of silicon is left at 500 ecm per minute

and with an etching of germanium 1.41 per minute compared to hydrofluoric acid,

permanent material 40. Stage 4 shows the flake after under these conditions it will be about 0.3 microns

etching the silicon oxide in hydrofluoric acid silicon and about 1.0 micron germanium per minute

and after removal of the opposite of the fluorinated water io etched away.

acid-resistant material from the remaining If enough material away from the platelets-silicon oxide41. Stage 5 shows the wafer 38 after which has been etched, the process is through slow Etching with gas containing hydrogen chloride with switching down the HF energy for the purpose of cooling the mesa bumps 42 under the silicon oxide 41st of the platelets. The hydrogen chloride gas and In Fig. 6 is the silicon oxide, for example through 15 the hydrogen gas will then be in that order Hydrogen fluoride vapor, removed again. The platelet is shut off, and the chamber is filled with nitrogen Can be flushed with relatively concentrated hydrogen fluoride. After at least 3 minutes, the steaming can be done the exclusion bell is not removed within the reaction chamber 1, and the etched platelets can be set as the chamber itself will soon be removed by etching away.

were. For this stage, therefore, another, not intended, 20 should be on the entire surface of the platelets Asked chamber made of polyethylene appropriate. To form an epitaxial film, this is how one proceeds However, the fact can be exploited that something different than after switching off the hydrogen chloride and hydrogen fluoride If the temperature of the substance rises, the system fumes with hydrogen for about 2 minutes and reacts faster with silicon oxide. Purged hydrogen fluoride gas and then evaporated the epitaxial growth can be strongly diluted with water.

be used cloth, if the wafer for loading target of silicon oxide used as a mask werschleunigung the reaction at its surface on the, the platelets may optionally be heated prior to about 100 ⁰ C. Under these circumstances, deposition of the oxide film with hydrogen chloride can be used in the quartz chamber, which is pre-etched because of the holding gas. The silicon film should be only slightly etched after it has been heated to a small extent, free of water, dense, coherent and over 1000. After making the collector zone by etching, be Ängström units thick. For example, the platelets are clean because the etching products are volatile on silicon oxide by oxidizing in silicon. Oxygen or water vapor atmosphere at 750 to

If the gas etching is carried out correctly, 1200 ° C will remain. By hydrolyzing 35 Silicon tetrachloride vapors can contain a silicon oxide, is generally even improved. After film are formed on silicon as on germanium, After lapping or polishing, the platelets are removed from the platelets using trichlorethylene vapor degreased, washed in alcohol by etching away the silicon oxide in these places and rubbed dry with cotton. The clean exposed. To do this, the silicon oxide is added to these Platelets are placed on a plate of melted 40 specific spots with a quartz made of hydrogen fluoride 3 laid, which covers a graphite base 4 covered acid non-vulnerable agent, and that The graphite base is about the size of a platelet for etching away the exposed SiIi-0.94 X 5.1 x 8 inches, and the quartz pad is placed about zium oxide in dilute hydrofluoric acid. 0.15 cm thick. Then it is rinsed in water and dried,

After placing the platelets, quartz and 45 and the covering medium are supported by a suitable underlay located in the district of the drive surrounded by the coil. The platelet is then thoroughly subjected to the reaction chamber 1 introduced. A not shown cleans.

Quartz base is provided in the reaction chamber The platelets are placed in the same way as before and keeps the base and the quartz overlay at a standing angle during the etching process from about 6 ° to the longitudinal axis of the reaction game described, introduced into the reaction chamber, chamber, as in FIG. 1 shown. It has been found, From that point on, the procedure is the same as that that this small angle increases the evenness of the etch when etching an uncovered plate. Even Process and also the growth of the epitaxial flow velocities and temperatures promotes table substance. they are the same.

After loading, the system is then etched to the desired depth

Put the end cap 8 on the reaction chamber, the wells can be epitaxially grown

mer 1 closed. Air will be filled from the reaction chamber- silicon or germanium. By means of this

mer 1 flushed out using dry nitrogen. In embodiments of the method in the

an internal diameter of the chamber of 74 mm and FIG. 3 to 9 and similar structures produced

a length of about 1 meter it will be put by a 60.

Flushing with 61 nitrogen per minute for 3 minutes was good

cleans. Gas is a very clean process, it would be beneficial to that

As the hydrogen flows in, exposed semiconductor junctions with a film are immediately made

started after switching off the nitrogen. Protect in case of silicon oxide before the freshly etched

In the exemplary embodiment for silicon, material is normally taken from the etching chamber 1,

sometimes 321 hydrogen flow in per minute, F i g. 9, in which the stage 1 is a section of the in F i g. 8 ge

for germanium 25.41 per minute. Then the showed stage 5 is showing another method of loading

After switching on the HF generator, platelets are used to form a mesa. In Fig. 9, level 1, is the

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Surface of the mesa elevation 42 of the plate 38 forms surface silicon oxide. The silicon oxide is covered with silicon oxide. Usually has a Mesaan- formation can be by heating the wafer to an order, a semiconductor region 43 are accelerated from opposite temperature below 200 ⁰ C. Type of conductivity so that a pn connection is formed. If the platelets are heated too much, however, they are lost. In stage 2, the water deviates from its surface on the surface of the plate, and a silicon oxide film 45 is formed around the surface, so that the transmission proceeds imperfectly.
aisle 44 is not exposed. The silicon oxide can be applied to the wafer in several ways by etching with gas containing hydrogen chloride, or it can also be used as a treatment for semiconductors without removing it from the reaction material directly in front of the solid-state diffusion chamber. There is one procedure, and occasionally thereafter. This treatment that, if the wafers are made of silicon, moisture can normally be admitted into the chamber in the same device. This is done like diffusion. F i g. 12 shows in such a way that after switching off the chlorine shows the in F i g. 1, but hydrogen is passed through water to hydrogen, so additionally containing a doping material that it is saturated before it then enters the reaction tank 53, valves 54 and 55 and a chamber. Flow meter 56 provided so that the doping

The in F i g. The device shown in FIG. 10 is a waste material in measured amounts in the reaction transformation of the device shown in FIG. 1 shown execution chamber 1 can be inserted over the hot form. The modifications consist in adding a platelet 2 and its properties usual laboratory fluid reservoir 47 and 20 by means of solid-state diffusion of the in the doping pre-valves 46 and 48 parallel to the hydrogen valve 17.

After etching changes with containing hydrogen chloride. Etching is done with hydrogen chloride containing gas if a silicon oxide film is formed, the gas is carried out immediately before diffusion, The aim is to keep the silicon wafers hot by making the surface extremely clean and for diffusion Leaves RF energy switched on. The valve 10 for 25 sion is ideal because of the speed with which the doping shutdown the hydrogen chloride is closed material penetrates the platelets on their surface, and the chamber 1 is purged with hydrogen gas. is the same over the entire platelet surface if The valves 46 and 48 of the template are opened and the template is made of the same material throughout, i.e. H. free the hydrogen valve 17 is closed so that water is from foreign matter. In addition, the substance due to the water 30 contained in the template 47 of a surface with a strong dopant content, before it gets into the reaction chamber. The centration by etching the surface with gaseous silicon oxide will be reduced on the surfaces of the platelets according to hydrogen chloride, the the formed while this still contains excessive dopant concentration in the reaction chamber are located so that the cleanliness of the surface part is removed and a new upper hydrogen chloride treated transition area remains with a lower concentration, remain. This is useful in that it is a change in the

Silicon oxide films and other metal oxide films have electrical resistance, dielectric strength,

also after hydrogen chloride etching without surface recombination velocity and other

further on semiconductor wafers in place of their surface properties,

if the in F i g. Apparatus 40 shown in FIG. 10 The operating conditions of the embodiments

according to FIG. 11 by adding the invention, for example, should be optimal or almost optimal,

a supply of metal halide vapor can be further removed and under the conditions described

is changing. Silicon oxide films, which are particularly useful, silicon and germanium with considerable accuracy

bar, can be etched on silence at low temperatures, with a high degree of flatness

zium and germanium platelets are formed, while maintaining their 45 and surface perfection. the

which under suitable conditions silicon tetra flatness is completely retained except at the outermost

exposed to chloride fumes. In Fig. 11 is to edges, · these are slightly rounded. The upper

the in F i g. 10 a liquid surface roughness is from the highest to the

Ability template 49 with silicon tetrachloride, a flow depth measured 0.2 microns. Up to forty

indicator 50, a measuring valve 51 and a shut-off valve 52 50 simultaneously etched platelets fluctuates through the

has been added. Change in thickness caused by etching by at most

After the silicon or germanium in the 3 ° / ₀ .

Chamber has been etched and cooled, the deviation of the change in thickness of two below

the chamber is etched for a few minutes with stick- the same conditions for batches etched in this way

fabric rinsed. The valve 17 is then closed, 55 amounting to a maximum of 5 ° / ₀ .

and the two veins leading to the water seal 47 can satisfactorily etch including flat etching Tiles 46 and 48 are opened so that with water within fairly wide ranges of temperatures, saturated nitrogen enters the reaction chamber. Hydrogen Chloride Concentrations and Gas Flow - The silicon tetrachloride shutoff valve is slowed down be made. This opened, and by admitting measured quantities 60 conditions are shown in the table. The chlorine nitrogen In the pre-hydrogen concentration filled with silicon tetrachloride there is that in a gaseous one position 49 by means of the measuring valve 51 and the flow mixture of hydrogen chloride and hydrogen entanzeigers 50 is the percentage more saturated with silicon tetrachloride. As the flow velocity is Nitrogen formed. The silicon tetrachloride vapor and the value given that you get when you use the the water vapor is directed into the reaction chamber. where the water from the platelet surface mixes hydrogen chloride and hydrogen through sorbed and the silicon tetrachloride from this the cross section of the reaction chamber at the point where Water is hydrolyzed, so that the Gasätzuag takes place on the plateau, divides.

conditions

temperature

HCl concentration

Gas flow rate

Germanium

760 to 945 ⁰ C
0 to 100%
0.3 to 25 cm / sec

silicon

900 to 1435 ° C Obis 100% 0.3 to 25 cm / sec

Under these conditions, the etching speed for germanium and silicon can be reached set between 0 and 0.25 mm / min.

Claims (13)

Patent claims: 1. Process for the production of layered semiconductor crystal elements, such as B. transistors or the like, using the etching of semiconductor crystal surface Q in a reaction chamber by means of a flowing hydrogen chloride containing gas mixture with heating of the element to increased, but below his Melting point lying temperature and subsequent aftertreatment in the same reaction chamber, characterized in that the semiconductor crystal surfaces with a gas mixture of hydrogen chloride and hydrogen Treated in a defined controllable ratio and then the surfaces in the reaction chamber provided with an epitaxial layer or a metal oxide cover layer or a solid-state diffusion undergoes. 2. The method according to claim 1, characterized in that surfaces of semiconductor crystals which are made of silicon or germanium. 3. The method according to claim 1, characterized in that the surfaces of the semiconductor crystal element before a selective etching in the reaction chamber with an adhesive, opposite the mixture of hydrogen chloride and hydrogen resistant, provided with openings cover layer coated with metal oxide. 4. The method according to claims 1 to 3, characterized in that the surface of the semiconductor crystal element is coated with a metal oxide consisting of silicon oxide or germanium oxide. 5. The method according to claim 3, characterized in that the semiconductor crystal element after etching to form a metal oxide layer, a flowing mixture of metal halide vapor and exposing it to water vapor at a temperature sufficient to form a metal oxide overcoat sufficient. 6. The method according to claims 4 and 5, characterized in that the semiconductor crystal element is treated with a metal halide vapor consisting of silicon tetrachloride. 7. The method according to claim 3, for the treatment of semiconductor crystal elements made of silicon material, characterized in that the semiconductor crystal element is ^{heated to a temperature above 800 0} C after the etching and treated with water vapor to form a silicon oxide cover layer. 8. The method according to claims 1 to 7, characterized in that the semiconductor crystal element to form an epitaxial layer on its surface after etching in the Reaction chamber a flowing mixture of hydrogen gas and silicon tetrachloride or germanium tetrachloride exposed and heated at the same time. 9. Process according to claims 1 to 8, characterized in that one is on the semiconductor crystal element to form a pn junction after the selective etching in the reaction chamber forms semiconductor material epitaxially on the etched crystal surfaces. 10. The method according to claim 9, characterized in that that one etches depressions in the semiconductor crystal element and then through them epitaxial growth fills with semiconductor material. 11. The method according to claims 1 to 7, characterized in that the semiconductor crystal element after etching a flowing gas containing a doping material and at the same time a gas that is high, below its melting point exposed to lying temperature. 12. The method according to claims 1 to 11, characterized in that the semiconductor crystal elements arranged as a plate on a flat surface, which is placed at a small angle introduces inclined into the reaction chamber, so that the platelets through the reaction chamber passing gas are opposite. 13. The method according to claims 1 to 12, characterized in that the support of the Semiconductor crystal element heated inductively. 1 sheet of drawings