DE3004009A1 - ELECTRICITY LADDER AND PRODUCTION METHOD DAFUER - Google Patents

Description

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Energy Conversion Devices, Inc. 1675 West Maple Road Troy, Michigan 48084 UNITED STATES.

Electric conductors and manufacturing processes therefor

030032/0848

3004008

/ T-

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Electric conductors and manufacturing processes therefor

The synthesis of analytically pure single crystals, which are suitable for solid-state investigations, of the covalent polymeric metallic Conductor, polymeric sulfur nitride (SN) is in the publication "Journal of the American Chemical Society "/ 97: 22 / Oct. 29, 1975, under the heading" Synthesis and Structure of Metallic Polymeric Sulfur Nitride, (SN), and its precursor, Disulfur Uinitride,

S ₂ N ₂ "by the authors CM. Mikulski, P.3. Russo, MS Saran, AGMacDiarmid, AF Garito and A.3. Heeger. The (SN) crystals were obtained in that

man S _? Np crystals were allowed to grow carefully and slowly at 0 C from the vapor phase over a period of 4-8 h, after which solid-state polymerization took place over a period of 60 h at room temperature. The polymerization was terminated by heating to 75 ° C. for 2 h. The (SN) crystals thus obtained are ordered by a

^x
spatial arrangement formed by parallel (SN) fibers,

030032/0848

3004003

-τ -

which consists of a nearly planar chain of sulfur and nitrogen atoms, and e ^{i is} obtained inen anisotropic crystalline structure.

In contrast, the object of the invention is to provide an electrical conductor which is formed by depositing a layer of amorphous (non-crystalline) conductor material containing amorphous polymeric sulfur nitride (SN) on a substrate. In this context, an electricity conductor and amorphous conductor material is to be understood as a conductor or a material that can be metallic, such as a semiconductor with a narrow bandwidth, a degenerate semiconductor or the like, which are good conductors of electricity. The deposition is preferably carried out by "plasma or glow discharge cleavage of hydrogen sulfide, HS, in a partial vacuum with an atmosphere containing _{ammonia gas NH or nitrogen gas N?"}

The dejected amorphous conductor of electricity according to the Invention with the amorphous polymeric sulfur nitride (SN) is not crystalline as in the aforementioned publication, since it does not have an ordered spatial arrangement of has parallel (SN) fibers or chains as in the publication. All fibers or chains or rings of Sulfur and nitrogen atoms in the amorphous conductor would be basically random and not crystalline as in the publication. X-ray spectrographs Investigations show that the layers according to the invention are amorphous. Here is the manufacturing process for this amorphous electricity conductor, it is cheaper and less time consuming and does not require so complicated Process steps such as the manufacturing process of the crystalline conductor according to the publication.

030032/0848

BATH ORIGINAL

30OA0OS

When the amorphous conductor material is deposited after the Invention by plasma or glow discharge cleavage can be capacitively coupled or inductively coupled System application. For example, in this one Explanation given a capacitively coupled system. The plasma jet can be caused by a high frequency discharge at z. B. 13, i> 6 MIIz or by applying a DC voltage to be triggered. The precipitation parameters are changeable and controllable so that a desired plasma or Glow discharge cleavage and a desired deposition of the amorphous conductor material can be obtained, where the rate of precipitation depends on these parameters. For example, the ratios of Ammonia gas (NH ^) or nitrogen gas (N-) to hydrogen sulfide (HpS) move between the following values:

1 y ^NH 3 s 20. 1 ^. ^N 2 ^ 20 .. _uc . . . .

Yq <Tj-Q < ύ— and "2Q- <77 — ο; · < Ύ ~> the HF power can be between 20 and 150 W, or the DC voltage can be up to 1000 V, the splitting or" suppression total pressure can be between 50 and 2000 microns pressure and the low overstruck temperature can be between room temperature and 300 ⁰ C.

One of the essential properties of the amorphous conductor layer according to the invention is its high conductivity; it has a specific electrical conductivity <o of more than l (-ilcm) ". Further, it has a very narrow energy band and a bandgap Eg of about 0.2 eV and a corresponding value Eo. of about 0.8 eV determined by the energy hi) when the optical absorption coefficient -OC is 10 cm, which is related to such a narrow energy band, and the film has a small activation electric energy ΔΕ of less than 0.1 eV.

030032/0848

BATH ORIGINAL

3004003

Furthermore, it has a high work function which is comparable to that of platinum and the like. B. with a thickness of a few K upwards. The substrate can be any desired substrate, e.g. B. od a non-conductor, a semiconductor. Like. Be.

The amorphous conductor of electricity according to the invention is versatile, for. B. generally as a conductor of electricity, as a superconductor, as electrodes or as contacts for current regulating and generating devices and the like, due to its stated essential properties it works very well as a Schottky barrier contact in solar cell or photoelectric energy conversion devices with semiconductor materials contained in the substrate, as it has a high quiescent current characteristic and a has a high no-load voltage characteristic. He is suitable especially very good for this purpose if the semiconductor materials are also amorphous. When amorphous Electric conductors according to the invention in solar cells or photoelectric energy conversion devices are used, they form inexpensive Schottky barrier contacts compared to platinum, gold and similar contacts commonly used.

It is believed that the high electronegativity is a Factor for a high work function characteristic in contacts for a Schottky barrier device od. like. is. In a further embodiment of the invention it is provided that the solid amorphous conductor according to the invention a small amount of fluorine (F) is added, which has one of the highest electronegativity in order to increase the electronegativity

030032/08 48

3QQ40QS

and increase the work function of the amorphous conductor and obtain a higher Schottky barrier potential, when the amorphous conductor is used as a Schottky barrier layer contact. The fluorine can be obtained by adding Fluorine gas F ~ to the ammonia gas or nitrogen gas containing Atmosphere can be added during the plasma or glow discharge cracking of the hydrogen sulfide.

According to the invention, an electricity conductor is through Deposition of a layer of solid amorphous conductor material, the amorphous polymeric sulfur nitride (SN) contains, produced on a substrate. The knockdown preferably takes place by plasma or glow discharge cleavage of hydrogen sulfide in a partial vacuum an atmosphere containing ammonia gas or nitrogen gas .

The invention is explained in more detail, for example, with the aid of the drawing. Show it:

Fig. 1 shows a device for the plasma or glow discharge cleavage of gases for Defeat the according to the invention Layer of amorphous solid conductor material on a substrate;

Figure 2 is a larger partial view of the layer deposited on a substrate amorphous conductor material, the substrate z. B. is a non-conductor; and

Fig. 3 is a view similar to Fig. 2, the substrate being a semiconductor as it is in a Schottky barrier device '.

030032/0848

BATH

300400a

-Al-

The device according to Fiy. 1 to knock down the solid amorphous conductor material by plasma or glow discharge deposition comprises a housing 10 which has a negative pressure chamber 11, an inlet chamber 12 and an outlet chamber 13 having. A cathode support 14 is in the vacuum chamber 11 inserted through an insulator 15 and circumferentially of an insulating sleeve 16 and a dark space shield 17 surrounded. At the inner end of the cathode support 14 is a Substrate 18 secured with a holder 19 which is screwed onto the cathode support 14 in electrical contact therewith is. The cathode carrier 14 has a recess for receiving an electrical heating element 20, which heats it, and a recess for receiving a temperature sensor for detecting the temperature of the cathode carrier 14. The temperature sensor 21 is in connection with the controller the energy supply to the heating element 20 used to the To keep the cathode carrier 14 and thus the substrate 18 at desired selected temperatures.

Furthermore, the device comprises an electrode or anode 23 in the vacuum chamber 11 of the housing 10 at a distance from the cathode carrier 14 is arranged. The anode 23 has a shield 24, which in turn is a substrate 25 can carry. The anode 23 is also provided with a recess for receiving an electrical heating element 26 and a further recess for receiving a temperature sensor 27 is formed. The temperature sensor 27 is in Connection with the control of the energy supply to the heating element 26 is used to maintain the anode 23 and thus the substrate 25 at desired selected temperatures. The space in the vacuum chamber 11 between the cathode carrier 14 and the anode 23 is used to generate a Glow discharge between the two so that a plasma reaction can take place. The cathode carrier 14 is provided with an energy

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Supply electrically connected, which can be either an HF or a DC voltage offset and can be regulated is, and the anode 23 is grounded so that the desired plasma or glow discharge conditions between both can be generated. The vacuum chamber 11 is by a vacuum pump 30 through the discharge chamber 13 and a Partial trap 31 evacuated, and a pressure gauge 32 shows the negative pressure in the negative pressure chamber 11; the pressure gauge is used in connection with the regulation of the vacuum pump.

The inlet chamber 12 of the housing 10 preferably has a A plurality of lines 34-, two of which are shown to be To conduct gases into the housing 10, in which they are mixed, after which they in the vacuum chamber 11 by Plasma or glow discharge cleavage between the cathode support 14 and the anode 23, which the substrates 18 and wear, be knocked down. If desired, the Inlet chamber 12 may be provided at a more remote location so that the gases are premixed there before they are passed into the vacuum chamber 11. The gases are fed to lines 34 through filter or cleaning units fed under control by shut-off devices 36. The shut-off devices determine the gas throughput into the vacuum chamber 11. The inlet chamber 12 and the outlet chamber 13 have shields 4-2 so that the plasma jet in the Vacuum chamber 11 is mainly enclosed between the cathode support 14 and the anode 23. By the ducts 34 supplied gases in the inlet chamber 12 are mixed, the plasma or glow discharge cleavage between the cathode support 14 and the anode 23 Subjected in the vacuum chamber 11, so that the desired, desired plasma or glow discharge cleavage and the Depositing the solid amorphous conductor material on the Substrates 18 and / or 25 takes place.

030032/084 3

In operation of the apparatus of FIG. 1, the system is first pumped to a pressure of less than about 5-10 µm prior to deposition. Hydrogen sulfide gas (H ₂ S) is passed through one of the lines 3k and another gas, e.g. B. ammonia gas (NH,) or nitrogen gas (N_) is passed through a further line 3 * t into the inlet chamber 12, where the two gases are premixed. The ratio of ammonia gas or nitrogen gas to hydrogen sulfide gas is changeable, e.g. B.

1 NH-j -Q ■. 7 ? 0

■ jq <C Tj-c ^ Y ~ ^and d jk < Tj-c ^ τ-> where particularly good results are achieved if the ratio is chosen to be greater than 1: 3. The gas mixture is fed with a constant ratio and constant throughput into the vacuum chamber 11, the partial pressure of which is kept in the range of approx. 50-2000 μm, preferably in the range of approx. The partial pressure in the negative pressure chamber 11 and the gases conducted into it create an atmosphere in the chamber which contains such gases. In this atmosphere, a plasma reaction is triggered between the cathode carrier IA and the anode 23, either by means of a direct voltage of up to approx. 1000 V or by means of HF energy in the range of 20-150 W, preferably approx. 50 W, operating at a frequency of approximately 13.56 MHz or some other desired frequency. The precipitation temperature can be varied between essentially room temperature and 300 ° C., with good results being achievable with essentially room temperature.

For example, a gas mixture of NH ^ / H _? S split in a ratio of 1: 3 by RF energy of 50 W in a partial pressure of 180 .mu.m, so that on the substrate 18 an amorphous

030032/0848
BATH

(SN) conductor layer was deposited with a thickness of 300 Λ. As a further example, a gas mixture of NHU / HS in a ratio of 4: 5 was split by HF energy of 50 W at a partial pressure of 4-70 μm, see above
that on the substrate an amorphous (SN) conductor layer
was knocked down with a thickness of IbOO A. Furthermore, a gas mixture of NH ^ / H_S in a ratio of 1: 2 was split by HF energy of 50 W at a partial pressure of 200 μm, and an amorphous (SN) conductor layer with a thickness of 700 8 was deposited on the substrate. These layers were all deposited at essentially room temperature and were all essentially black. They were found to be amorphous by X-ray spectroscopy. They had a specific electrical conductivity of more than 1 (_flcm) ~, an electrical one
Activation energy of less than 0.1 eV and an energy or bandal
of about 0.8 eV.

energy or band gap of approx. 0.2 eV and a value Eo.

If a small amount of fluorine (F) is to be incorporated into the amorphous conductor layer, this can be done by the
Atmosphere in the vacuum chamber 11, which contains ammonia or nitrogen gas, while the plasma or glow discharge cleavage of the hydrogen sulfide is supplied through a further line 34 fluorine gas (F_).

2 shows a layer 48 of solid amorphous semiconductor material with amorphous polymeric sulfur nitride (SN) which has been deposited on the substrate 18, which is a dielectric, by the method indicated. For example, can
the substrate 18 made of glass, plastic or another
Insulating material exist.

Fig. 3 shows a Schottky barrier solar cell, wherein the substrate 18 comprises a semiconductor material. Here, the substrate may be a metal substrate 50 to which at 52

030032/0848

a semiconductor layer 51 is applied. Z. II. can the Semiconductor layer 51 be crystalline silicon or another semiconductor material, and to "make a good ohmic contact To ensure between the semiconductor layer 51 and the me-metallic substrate 50, the layer is highly doped, such as is indicated at 51 '. The layer of solid amorphous conductor material 48 after the invention is according to the specified method is applied to the semiconductor layer 51. The solid amorphous conductor layer 48 has the above specified characteristics including a good specific electrical conductivity and a high work function, and it is also transparent to radiation, including solar radiation. On the surface of the solid amorphous conductor layer 48 is a grid electrode 60 with good specific electrical conductivity. the The function of the grid electrode 60 is the uniform absorption of current from the amorphous conductor 4-8. Line anti-reflective coating 61, which is also radiolucent, is over the conductor layer 48 and the grid electrode 60 provided.

A Schottky barrier layer is at the interface 49 between the amorphous conductor layer 48 and the semiconductor material 51 formed. The SchotLky-SperrsehiehL creates a Space charge zone in the semiconductor material 51 which penetrates from the interface 49 into the latter. The space charge zone will also referred to as a depletion zone, and this preferably extends over the entire width of the semiconductor layer 51. Carriers generated somewhere in the layer 51 by the absorption of solar radiation are affected by the electric field entrained in the depletion zone and enter the metallic substrate 50 or the solid amorphous conductor layer 48, In this way, a photoelectric current is generated which flows into one with the metallic substrate 50 and the grid electrode 60 connected circuit can be fed.

Q30Q32 / 0848

BATH ORIGINAL

Claims (1)

Patent attorneys, iipL Ing.Hans -Jürgen MMer - 3 OO 4 OO ) r. rer. nat. Thomas Berendt. '. _; T ^ν Γ ^νν " Dr.-Ing. Hans Leyh ■ aeDeMüdie P ate -'η ta η sp f ü ch e ί 1. ) A method for producing an electric conductor, characterized in that a layer of a solid amorphous conductor material containing amorphous polymeric sulfur nitride (SN) by plasma or glow discharge cleavage of hydrogen sulfide (HpS) in a partial vacuum with a Ammonia (NH ₃ ) or nitrogen (N -) gas containing atmosphere is precipitated. 2. The method according to claim 1, characterized in that the atmosphere also contains fluorine gas (F _? ). 3. The method according to claim 1, characterized in that .the ratio of ammonia gas or nitrogen to Hydrogen sulfide between 1:20 and 20: 1 is chosen H. Method according to Claim 3, characterized in that the ratio is selected to be greater than 1: 3. 5. The method according to claim 1, characterized in that the atmosphere contains ammonia gas (NH ₃ ). 030032/0848 3004003 -Z- 6. The method according to claim 1, characterized, ' .-:-.. that the atmosphere contains nitrogen gas (N _? ). 7. The method according to claim 1, characterized, , that the plasma or glow discharge cleavage is triggered by high frequency energy. 8. The method according to claim 7, ■. · ■ - - characterized in that that the high frequency energy is essentially 13.56 MHz . '■■■■ - 9. The method according to claim 8, characterized that the power of high frequency energy between 20 and 150 W. . 10. The method according to claim 9, -. characterized, that the power of the high-frequency energy is approx. 50 W. 11. The method according to claim 1,
characterized, that the plasma or glow discharge cleavage is triggered by applying a direct voltage. 12. The method according to claim 11, characterized, * that the DC voltage is up to 1000 V. . 0 3 0032./08 4 8 , 13, method according to claim I ^ characterized in that that the total partial vacuum is between 50 and 2000 to 1 ^. Method according to claim 13, characterized in that the total vacuum is between 180 and A-70 µm 15. The method according to claim 1, characterized in that that the precipitation temperature is between essentially room temperature and 300 C. 16. The method according to claim 15, characterized in that that the precipitation temperature is essentially room temperature. 17. The method according to claim 1, characterized in that in the plasma or glow discharge cleavage capacitively coupled system is used. 18. The method according to claim 1, characterized in that that an inductively coupled system is used in the plasma or glow discharge cleavage. 19. The method according to claim 1, characterized in that a non-conductor is used as the substrate. 030032/0848 20. The method according to claim 1, characterized in that that a semiconductor is used as the substrate. 21. Electricity conductor,
characterized by a layer of solid amorphous conductor material with amorphous polymeric sulfur nitride (SN) deposited on a substrate. 22. Electricity conductor according to claim 21, characterized in that that the amorphous conductor material also contains fluorine (F). 23. Electricity conductor according to claim 21, characterized by a specific electrical conductivity of more as l (i "Lcm) ~. 24. Electricity conductor according to claim 21, marked by a, band gap of about 0.2 eV. 25. Electricity conductor according to claim 21, characterized, that the measure of its energy band, or band gap, is expressed as Eo., is about 0.8 eV. 26. Electricity conductor according to claim 21, characterized by an electrical activation energy of less than 0.1 eV. 030032/0848 30Q4009 27. Electricity conductor according to claim 21, characterized by a high work function. 28. Electricity conductor according to claim 21, characterized in that that the substrate is a non-conductor. 29. Electricity conductor according to claim 21, characterized in that that the substrate is a semiconductor. 30. Electricity conductor according to claim 21, characterized in that that the substrate is a semiconductor and the conductor of electricity thus forms a Schottky barrier layer junction. 31. Electricity conductor according to claim 22, characterized in that that the substrate is a semiconductor and the conductor of electricity thus forms a Schottky barrier junction. 32. Electricity conductor according to claim 21, characterized by a thickness in the A range. 030032/0848