GB2124826A - Amorphous semiconductor materials - Google Patents

Amorphous semiconductor materials Download PDF

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GB2124826A
GB2124826A GB08311175A GB8311175A GB2124826A GB 2124826 A GB2124826 A GB 2124826A GB 08311175 A GB08311175 A GB 08311175A GB 8311175 A GB8311175 A GB 8311175A GB 2124826 A GB2124826 A GB 2124826A
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band gap
alloy
amorphous silicon
oxygen
layer
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GB8311175D0 (en
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Vincent Cannella
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Energy Conversion Devices Inc
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Energy Conversion Devices Inc
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/16—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only elements of Group IV of the Periodic Table
    • H01L29/167—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only elements of Group IV of the Periodic Table further characterised by the doping material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/22—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/04—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/20—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof such devices or parts thereof comprising amorphous semiconductor materials
    • H01L31/202—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof such devices or parts thereof comprising amorphous semiconductor materials including only elements of Group IV of the Periodic Table
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Electromagnetism (AREA)
  • Photovoltaic Devices (AREA)

Abstract

Wide band gap p-type amorphous silicon alloys having increased conductivities contain oxygen as a band gap increasing element. Other band gap increasing elements such as carbon can also be incorporated in minor amounts. The alloys also incorporate at least one density of states reducing element such a fluorine and/or hydrogen. The compensating or altering element and other elements such as a p-type dopant boron can be added during deposition by glow discharge decomposition. Incorporation of oxygen in concentrations of one to thirty percent results in band gaps of 1.7eV to greater than 2.0eV. For a given band gap, the present alloys exhibit conductivities substantially greater than prior wide band gap p amorphous silicon alloys incorporating carbon alone as a band gap increasing element. The wide band gap p amorphous silicon alloys are particularly useful in photoresponsive devices. A p-i-n photovoltaic cell comprises a back reflector 114, a wideband gap P+ type layer 116, a thick intrinsic layer 118 and an N+ type layer 120 topped with a transparent conductive oxide 122; a grid electrode 124 and an antireflection layer 126. Bandgap reducing elements such as Ge, Sn, or Pb may be incorporated in the intrinsic layer 118 and a graded bandgap structure may be produced. The positions of the P+ and N+ type layers may be intercharged (Fig. 5) and a pair of cells may be stacked in a tandem configuration (Fig. 6). <IMAGE>

Description

SPECIFICATION Photovoltaic devices and manufacture thereof This invention relates to photovoltaic devices and a method of making the same wherein the devices are formed from layers of amorphous semiconductor alloys.
Silicon isthe basis ofthe huge crystalline semicon- ductor industry and is the material which has produced expensive high efficiency (18 percent) crystalline solar cellsfor space applications. For terresterial applications, the crystalline solar cells typically have much lower efficiencies on the order of 12 percent or less. When crystalline semiconductor technology reached a commercial state, it becamethefoundation of the present huge semiconductor device manufacturing industry.Thiswas due to the ability ofthe scientistto grow substantially defect-free germanium and particularly silicon crystals, and then turn them into extrinsic materials with p-type and n-type conductivity regions therein.This was accomplished by diffusing into such crystalline material parts per million of donor (n) or acceptor (p) dopant materials introduced as substitutional impurities into the substantially pure crystalline materials, to increase their electrical conductivity and to control their being either of a porn conduction type. The fabrication processes for making p-n junction crystals involve extremely complex, time consuming, and expensive procedures.
Thus, these crystalline materials useful in solar cells and current control devices are produced under very carefully controlled conditions by growing individual single silicon or germanium crystals, and when p-n junctions are required, by doping such single crystals with extremely small and critical amounts of dopants.
These crystal growing processes produce such relatively small crystals that solar cells require the assembly of many single crystals to encompass the desired area of only a singlesolarcell panel. The amount of energy necessary to make a solar cell in this process, the limitation caused by the size limitations of the silicon crystal, and the necessity to cut up and assemble such a crystalline material have all resulted in an impossible economic barrierto the large scale use ofcrystallinesemiconductor solar cells forenergy conversion. Further, crystalline silicon has an indirect optical edge which results in poor light absorption in the material. Because ofthe poor light absorption, crystalline solar cells have to be at least 50 microns thickto absorb the incident sunlight.Even ifthe single crystal material is replaced by polycrystalline silicon with cheaper production processes, the indirect optical edge is still maintained; hence the material thickness is not reduced. The polycrystalline material also involves the addition of grain boundaries and other defect problems, which defects are ordinarily deleterious.
In summary, crystal silicon devices have fixed parameters which are notvariable as desired, require large amounts of material, are only producable in relatively small areas and are expensive and time consuming to produce. Devices based upon amorphous silicon alloys can eliminate these crystal silicon disadvantages. An amorphous silicon alloy has an optical absorption edge having properties similarto a direct gap semiconductor and only a material thickness of one micron or less is necessary to absorb the same amount of sunlight as the 50 micron thick crystalline silicon. Further, amorphous silicon alloys can be made faster, easier and in larger areas than can crystalline silicon.
Accordingly, a considerable effort has been made to develop processes for readily depositing amorphous semiconductor alloys orfilms, each of which can encompass relatively large areas, if desired, limited only by the size of the deposition equipment, and which could be readily doped to form p-type and n-type materials where p-n junction devices are to be made therefrom equivalent to those produced by their crystalline counterparts. For many years such work was substantially unproductive. Amorphous silicon or germanium (Group IV) films are normallyfour-fold coordinated and were found to have microvoids and dangling bonds and other defects which produce a high densityof localized states in the energy gap thereof.The presence of a high density of localized states in the energy gap of amorphous silicon semiconductorfilms results in a low degree of photoconductivity and short carrier lifetime, making such films unsuitable for photoresponsive applica- tions. Additionally, such films cannot be successfully doped or otherwise modified to shiftthe Fermi level close to the conduction or valence bands, making them unsuitable for making p-njunctionsforsolarcell and current control device applications.
In an attempt to minimize the aforementioned problems involved with amorphous silicon (originally thoughtto be elemental),W. E. Spear and P. G. Le Comber of Carnegie Laboratory of Physics, University of Dundee, in Dundee, Scotland, did some work on "Substitutional Doping of Amorphous Silicon", as reported in a paper published in Solid State Communications, Vol. 17, pp.1193-1196,1975, toward the end of reducing the localized states in the energy gap in amorphous silicon to make the same approximate more closely intrinsic crystalline silicon and of substitutionally doping the amorphous materials with suitable classic dopants, as in doping crystalline materials, to make them extrinsic and of porn conduction types.
The reduction of the localized states was accomplished by glow discharge deposition of amorphous silicon films wherein a gas of silane (SiH4) was passed through a reaction tube where the gas was decomposed by an r.f. glow discharge and deposited on a substrate at a substrate temperature of about 500 6000K (227-327 C). The material so deposited on the substrate was an intrinsic amorphouse material consisting of silicon and hydrogen. To produce a doped amorphous material a gas of phosphine (PH3)for n-type conduction or a gas of diborane (B2H6) for p-type conduction were premixed with the silane gas and passed through the glow discharge reaction tube under the same operating conditions.The gaseous concentration of the dopants used was between about 5 x 1 o-6 and 1 of2 parts per volume. The material so deposited was shown to be extrinsic and of nor p conduction type.
While it was not known by these researchers, it is now known by the work of others that the hydrogen in the silane combines at an optimum temperature with many of the dangling bonds of the silicon during the glow discharge deposition, to substantially reduce the density ofthe localized states in the energy gap toward the end of making the electronic properties of the amorphous material approximate more nearly those of the corresponding crystalline material.
The incorporation of hydrogen in the above method however has limitations based upon the fixed ratio of hydrogen to silicon in silane, and various Si:H bonding configurations which introduce new antibonding states. Therefore, there are basic limitations in reducing the density of localized states in these materials.
Greatly improved amorphous silicon alloys having significantly reduced concentrations of localized states in the energy gaps thereof and high quality electronic properties have been prepared by glow discharge asfully described in U.S. Patent No.
4,226,898, Amorphous Semiconductors Equivalent to Crystalline Semiconductors, Stanford R. Ovshinsky and Arun Madan which issued October7. 1980, and by vapor deposition as fully described in U.S. Patent No.
4,217,374, Stanford R. Ovshinsky and Masatsugu Izu, which issued on August12, 1980, underthe same title.
As disclosed in these patents fluorine is introduced into the amorphous silicon semiconductor alloy to substantially reduce the density of localized states therein. Activated fluorine especially readily bonds to silicon in the amorphous bodyto substantially decrease the density of localized defect states, because the small size high reactivity of specification of chemical bonding ofthefluorineatomsenablesthem to achieve a more defectfree amorphous silicon alloy.
The fluorine bonds to the dangling bonds of the silicon and forms what is believed to be a predominantly ionic stable bond with flexible bonding angles, which results in a more stable and more efficient compensation or alteration than is formed by hydrogen and othercompensating or altering agents. Fluorine also combines in a preferable mannerwith silicon and hydrogen, utilizing the hydrogen in a more desirable manner, since hydrogen has several bonding options.
Withoutfluorine, hydrogen may not bond in a desirable manner in the material, causing extra defect status in the band gap as well as in the material itself.
Therefore, fluorine is considered to be a more efficient compensating or altering element than hydrogen when employed alone or with hydrogen because of its high reactivity, specificity in chemical bonding, and high electronegativity.
As an example, compensation may be achieved with fluorine alone or in combination with hydrogen with the addition of these element(s) in very small quantities (e.g., fractions of one atomic percent).
However, the amounts of fluorine and hydrogen most desirably used are much greaterthan such small percentages so as to form a silicon - hydrogen fluorine alloy. Such alloying amounts offluorine and hydrogen may, for example, be in the range of 1 to 5 percent or greater. It is believed that the alloy so formed has a lower density of defect states in the energy gap than that achieved by the mere neutraliza tion of dangling bonds and similar defect states. Such larger amount offluorine, in particular, is believed to participate substantially in a new structural configuration of an amorphous silicon-containing material and facilitatesthe addition of other alloying materials, such as germanium.Fluorine, in addition to its other characteristics mentioned herein, is believed to be an organizer of local structure in the silicon containing alloythrough inductive and ionic effects. It is believedthatfluorine also influences the bonding of hydrogen by acting in a beneficialwayto decrease the density of defect states which hydrogen contributes while acting as a density of states reducing element. The ionic role that fluorine plays in such an alloy is believed to bean importantfactorin terms ofthe nearest neighbor relationships.
Amorphous silicon alloys containing fluorine have thus demonstrated greatly improved characteristics for photovoltaic applications as compared to amorphous silicon alloys containing just hydrogen alone as a density of states reducing element. However, in orderto realize the full advantage ofthese amor phoussilicon alloys containing fluorinewhen used to form the active regions of photovoltaic devices Sit is necessaryto assure that the greatest portion ofthe photon absorption takes place therein for efficiently generating electron-hole pairs. The foregoing becomes especially important in the fabrication of photovoltaic devices ofthe p-i-n configuration.Devices ofthistype require the deposition of p and n-type doped layers before and after the deposition of an intrinsic layer. These doped layers, on opposite sides of the active intrinsic layer, wherein the electron-hole pairs are generated, establish a potential gradient across the device to facilitate the separation of the electrons and holes and also form contact layers to facilitate the collection of the electrons and holes as electrical current.
With this type of device structure, it is therefor importantthatthe p and n-type layers be highly conductive and, at least in the case of the p-type layer, have a wide band gap to decrease the photon absorption ofthe p-type layer and thus afford increased absorption in the active intrinsic layer. A p-type layer having a wide band gap is therefore extremely advantageous when forming the top layer ofthe device through which the sun energyfirst passes, or when forming the bottom layer of the device in conjunction with a back reflecting layer.
Back reflecting layers serve to reflect unused light back into the intrinsic region ofthe device to permit further utilization of the sun energy for generating additional electron-hole pairs. Awide band gap p-type layer permits a greater portion of the reflected lightto pass into the active intrinsic layer than a p-type layer not having a wide band gap Unfortunately, as the band gap of p-type amos phous silicon alloys is increased, the conductivity decreases. To be effective in a photovoltaic device a wide band gap p amorphous silicon alloy should have a band gap of 1.9eV or greater. Conventional p-type wide band gap amorphous silicon alloys containing silicon, hydrogen, boron, and carbon in high doping regimes exhibit conductivities of about 1 10-7 (Q -cm)-1.
With increased concentration of carbon to widen the band gaps, the resulting conductivity decreases.
The present invention provides a method of making a wide band gap p amorphous silicon alloy, said method comprising depositing on a substrate a material including at least silicon, incorporating in said material at least one density of states reducing element and a p-type dopant, and introducing a band gap increasing element into said material, said band gap increasing element being oxygen, to produce a p-type amorphous silicon alloy including oxygen in the range of one to thirty atomic percent.
The present invention further provides a wide band gap p amorphous silicon alloy, said alloy including silicon and incorporating at least one density of states reducing element and a p-type dopanttherein, the alloy further including at least one band gap increas ing element incorporated therein, said band gap increasing element being oxygen, and said alloy including said oxygen in the range of one to thirty atomic percent.
The present invention further provides a photore sponsive device of the type comprising superim posed layersofvarious materials including an amorphous semiconductor alloy body forming an intrinsic active photo responsive layer upon which radiation can impinge to produce charge carriers, the device including a wide band gap p amorphous silicon alloy layer adjacent said intrinsic layer includ ing at least one density of states reducing element, a p-type dopant, and at least one band gap increasing element, said band gap increasing element being oxygen, said wide band gap p amorphous silicon alloy including said oxygen in the range of one to thirty atomic percent.
The present invention further provides a multiple cell photovoltaic device formed from multiple layers of amorphous semiconductor alloys deposited on a substrate, said device comprising: a plurality of single cell units arranged in series relation, each said single cell unit comprising afirstdopedamorphous semiconductor alloy layer, a body of intrinsic amor phous semiconductor alloy deposited on said first doped layer, a further doped amorphous semicon ductor alloy layer deposited on said intrinsic body and being of opposite conductivity with respectto said first doped amorphous semiconductor alloy layer, and wherein at least one of said doped amorphous semiconductor alloy layers of at least one of said single cell units comprises a wide band gap p amorphous silicon alloy including at least one density of states reducing element, a p-type dopant, and at leastone band gap increasing element, said band gap increasing element being oxygen, and said wide band gap p amorphous silicon alloy including said oxygen in the range of one to thirty atomic percent.
The alloys of the present invention can be utilized in single cell photovoltaic devices ofthe p-i-n configura tion, and in multiple cell structures having a plurality of single cell units.
Preferablythe present invention provides new and improved wide band gap p-type amorphous silicon alloys having increased conductivitiesfor particular use in photoresponsive devices. The alloys of the present invention can be deposited by glow dis charge decomposition. In accordance with the pre sent invention the alloys may include oxygen as a band gap increasing element. The alloys can incorporate other band gap increasing elements such as carbon in minor amounts.
The amorphous silicon alloys may also incorporate at least one density of states reducing element such as fluorine and/or hydrogen. The compensating or altering elements and other elements can be added during deposition.
The wide band gap p-type amorphous silicon alloys of the present invention may further include a p-type dopant, such as boron. The boron can be incorporated into the alloy from diborane (B2H6) during the glow discharge deposition.
Thealloyscan incorporatethe band gap increasing element oxygen, in concentrations of one to thirty percent resulting in band gaps from 1 .7eVto greater than 2.0eV. Fora given band gap, the alloys of the present invention exhibit conductivities substantially greaterthan priorwide band gap p amorphous silicon alloys incorporating carbon alone as a band gap increasing element.
The wide band gap p amorphous silicon alloys of the present invention are particularly useful in photoresponsive devices such as p-i-n photovoltaic devices having an active region wherein photogenerated electron-hole pairs are created. Because the alloys have wide band gaps, relatively few photons are absorbed therein allowing a greater number of photons to be absorbed bythe active region. Hence, the advantages of amorphous silicon-fluorine alloys for the active regions may be realized. Since the alloys of the present invention have high conductivity, more efficient collection of the photogenerated electrons and holes as current results. Furthermore, the p-i-n photovoltaic devices incorporating the alloy of the present invention can include a back reflector to reflect unused light back into the intrinsic layer to provide additional photogenerated electron-hole pairs.
The short circuit current of the devices incorporating the alloy of the present invention may be further enhanced by adjusting the band gap of the active amorphous silicon alloys. Band gap adjusting elements can be added to the active or intrinsic alloys to adjustthe band gapsthereoforgradethe band gap of the entire intrinsic body. For example, band gap decreasing elements such as germanium, tin, or lead can be added to the intrinsic alloy body during deposition.
The devices and method of the present invention can also be utilized in the making of multiple cell devices, such as tandem cells. The band gaps ofthe intrinsic layers can be adjusted so thatthe current generating capability of each cell can be maximized for a given different portion ofthe sun light spectrum.
Embodiments of this invention will now be described by way of example with reference to the drawings accompanying this specification in which: Fig. is a diagrammatic representation of a glow discharge deposition system which may be utilized in practicing the method of the present invention for making the photovoltaic devices of the invention; Fig. 2 is a sectional view of a portion ofthe system of Fig. 1 taken along the lines of 2-2 therein; Fig. 3 is a graph illustrating the conductivity versus band gap for a conventional wide band gap p amorphous silicon alloy and for a wide band gap p amorphous silicon alloy made in accordance with the present invention; 5 Fig. 4 is a sectional view of a p-i-n photovoltaic device embodying the present invention; Fig. Sisasectionalviewofanotherp-i-n photovol taic device structured in accordance with a further embodiment of the invention; and Fig. 6 is a sectional view of a multiple solar cell incorporating a plurality of p-i-n photovoltaic cell units arranged in tandem configuration in accord ance with the present invention.
Referring now more particularly to Fig. 1, there is shown a glow discharge deposition system 10 including a housing 12. The housing 12 encloses a vacuum chamber 14 and includes an inlet chamber 16 and an outlet chamber 18. A cathode backing member20 is mounted inthevacuum chamber 14 through an insulator 22.
The backing member20 includes an insulating sleeve 24 circumferentially enclosing the backing member 20. A dark space shield 26 is spaced from and circumferentially surrounds the sleeve 24. A substrate 28 is secured to an inner end 30 ofthe backing member 20 by a holder 32. The holder 32 can be screwed or otherwise conventionally secured to the backing member 20 in electrical contactthere with.
The cathode backing member 20 includes a well 34 into which is inserted an electrical heater 36 for heating the backing member 20 and hence the substrate 28. The cathode backing member 20 also includes atemperature responsive probe 38 for measuringthetemperatureofthebacking member 20. The temperature probe 38 is utilized to control the energization of the heater 36 to maintain the backing member 20 and the substrate 28 at any desired temperature.
The system 10 also includes an electrode 40 which extends from the housing 12 into the vacuum chamber 14 spaced from the cathode backing mem ber 20. The electrode 40 includes a shield 42 surrounding the electrode40 and which in turn carries a substrate 44 mounted thereon. The elec trode 40 includes a well 46 into which is inserted an electrode heater 48. The electrode 40 also includes a temperature responsive probe 50for measuring the temperature of the electrode 40 and hence the substrate 44. The probe 50 is utilized to control the energization ofthe heater48to maintain the elec trode 40 and the substrate 44 at any desired temperature, independently of the member 20.
Aglow discharge plasma is developed in a space 52 between the substrates 28 and 44 by the power generated from a regulated R.F., A.C. or D.C. power source coupled to the cathode backing member 20 across the space 52 to the electrode 40 which is coupled to ground. The vacuum chamber 14 is evacuated to the desired pressure by a vacuum pump 54 coupled to the chamber 14through a particle trap 56. A pressure gauge 58 is coupled to the vacuum system and is utilized to control the pump 54to maintain the system 10 at the desired pressure.
The inlet chamber 16 of the housing 12 preferably is provided with a plurality of conduits 60 for introduc ing materials into the system 10 to be mixed therein and to be deposited in the chamber 14 in the glow discharge plasma space 52 upon the substrates 28 and 44. If desired, the inlet chamber 16 can be located at a remote location and the gases can be premixed priortobeingfed into the chamber 14. The gaseous materials are fed into the conduits 60through a filter or other purifying device 62 at a rate controlled by a valve 64.
When a material initially is not in a gaseousform, but instead is in a liquid or solid form, it can be placed into a sealed container 66 as indicated at 68. The material 68then is heated by a heater 70 to increase the vapor pressure thereof in the container 66. A suitable gas, such as argon, is fed through a dip tube 72 into the material 68so asto entrapthevapors of the material 68 and conveythe vapors through a filter 62' and a valve 64' into the conduits 60 and hence into the system 10.
The inlet chamber 16 and the outlet chamber 18 preferably are provided with screen means 74to confine the plasma in the chamber 14 and principally between the substrates 28 and 44.
The materialsfedthrough the conduits 60 are mixed in the inlet chamber 16 and then fed into the glow discharge space 52 to maintain the plasma and deposit the alloy on the substrates with the incorpora tion of silicon, fluorine, oxygen and the other desired alterant elements, such as hydrogen, and/or dopants or other desired materials.
In operation, and for depositing layers of intrinsic amorphous silicon alloys, the system 10 is first pumped down to a desired deposition pressure, such as less than 20 mtorr priorto deposition. Starting materials or reaction gases such as silicon tetraf luoride (SiF4) and molecular hydrogen (H2) and/or silane are fed into the inlet chamber 16through separate conduits 60 and are then mixed in the inlet chamber. The gas mixture is fed into the vacuum chamberto maintain a partial pressure therein of about .6torr. A plasma is generated in the space 52 between the substrates 28 and 44 using either a DC voltage of greaterthan 1000 volts or by radio frequency power of about 50 watts operating at a frequency of 13.56 M Hz o r other desired frequency.
In addition to the intrinsic amorphous silicon alloys deposited in the manner as described above, the devices ofthe present invention as illustrated in the various embodiments to be described hereinafter also utilize doped amorphous silicon alloys including the wide band gap p amorphous silicon alloy ofthe present invention. These doped alloy layers can be p, p+, n, or n+ type in conductivity and can be formed by introducing an appropriate dopant into the vacuum chamber along with the intrinsic starting material such as silane (SiH4) or the silicon tetraf luoride (SiF4) starting material and/or hydrogen and/or silane.
For nor p doped layers, the material can be doped with 5to 100 ppm of dopant materials as it is deposited. For n+ or p+ doped layers, the material is doped with 100 ppm to over 1 percent of dopant material as it is deposited. The ndopants can be phosphorus, arsenic, antimony, or bismuth. Prefer ably, then doped layers are deposited by the glow discharge decomposition of at least silicon tetraf luoride (SiF4) and phosphine (PHs). Hydrogen and/or silane gas (SiH4) may also be added to this mixture.
The p dopants can be boron, aluminum, gallium, indium, orthallium. Preferably, the p doped layers are deposited by the glow discharge decomposition of at least silane and diborane (B2H6) or silicon tetrafluoride and diborane. To the silicon tetrafluoride and diborane, hydrogen and/orsilane can also be added.
In addition to the foregoing, and in accordance with the present invention, the p doped layers are formed from amorphous silicon alloys containing oxygen as a band gap increasing element. Hence, to each of the gas mixtures indicated above, oxygen diluted with argon is added to the gas m ixtu res. For example, a wide band gap p amorphous silicon alloy can be formed by a gas mixture of (in percentages by volume)94% silane (SiH4), 5.2% diborane (B2H6), and .20/a oxygen. This results in a p-type amorphous silicon alloy having a band gap greaterthan 1.9eV.
The .2% oxygen is obtained by diluting the oxygen with argon. This level of oxygen in the gas phase results in an amorphous silicon alloy incorporating about 10 atomic percent oxygen in the film.
Various gas mixtures can be utilized with the oxygen representing from .01 to 1 percent by volume ofthe gas mixture. This range correspondingly results in from 1 to 30 atomic percent oxygen concentrations in the deposited films. These concentrations of oxygen result in band gaps ranging from 1.7eV to greaterthan 2.0eV.
The increase in conductivity ofthe new and improved alloys of the present invention may be best seen in Fig. 3. Here, the conductivity versus band gap is plotted forthe new alloys containing oxygen as a band gap increasing element and forthe conventional wide band gap p amorphous silicon alloy containing carbon alone as a band gap increasing element. It will be noted that fora given band gap, the new alloy has a conductivity which is substantially greater than the conventional alloy. It has also been observed that wide band gap p amorphous silicon alloys containing both oxygen and carbon exhibit greaterconductivi tiesthan those incorporating carbon alone as a band gap increasing element. However, in those films, only minor amounts of carbon was incorporated in the alloy compared to the amount of oxygen.From the foregoing, it can be seen that oxygen not only serves as a band gap increasing element in p-type amorphous silicon alloys, but also that wide band gap p-type amorphous silicon alloys including oxygen as the band gap increasing element exhibit higher conductivitiesthan prior wide band gap p-type amorphous silicon alloys not including oxygen.
The doped layers of the devices are deposited at various temperatures in the range of 200into about 1000 C, depending upon theform of the material used and the type of substrate used. For aluminum substrates, the uppertemperature shoud not be above about 600"C and for stainless steel it could be above about 1000 C. For the intrinsic and doped alloys initially compensated with hydrogen, as for examplethosedepositedfrom silane gas starting material, the substrate temperature should be less than about 4000C and preferably between 2500C and 350 C.
Other materials and alloying elements may also be added to the intrinsic and doped layers to achieve optimized current generation. These other materials and elements will be described hereinafter in connection with the various device configurations embodying the present invention illustrated in Figs. 4through 6.
Referring nowto Fig. 4, it illustrates in sectional view a p-i-n device structured in accordance with a first embodiment of the present invention The device 110 includes a substrate 112 which may be glass or a flexible web formed from stainless steel or aluminum. The substrate 112 is of a width and length as desired and preferably3 milsthick.
An electrode 114 is deposited upon the substrate 112 to form a back reflectorforthe cell 110. The back reflector 114 is deposited by vapor deposition, which is a relatively fast deposition process. The back reflector layer preferably is a reflective metal such as silver, aluminum, or copper. The reflective layer is preferable since, in a solar cell, non-absorbed light which passes through the device is reflected from the back reflector 1 14 where it again passes into the device which then absorbs more of the light energy to increase the device efficiency.
The substrate 112 is then placed in the glow discharge deposition environment. Afirst doped wide band gap p-type amorphous silicon alloy layer 116 is deposited on the back reflecting layer 114 in accordance with the present invention. The layer 116 as shown is p+ in conductivity. The p+ region is as thin as possible on the order of 50 to 500 angstroms in thickness which is sufficient for the p+ region to make good ohmic contact with the back reflector 114. The p+ region 116 also serves to establish a potential gradiant across the device to facilitate the collection of photo induced electron-hole pairs as electrical current. The p+ region 1 can be deposited from any of the gas mixtures previously referred to forthe deposition of such material in accordance with the present invention.
A body of intrinsic amorphous silicon alloy 118 is next deposited overthe wide band gap p-type layer 116. The intrinsic body 118 is relatively thick, on the order of 4500 , and is deposited from silicon tetrafluoride and hydrogen and/orsilane. The intrinsic body preferably contains the amorphous silicon alloy compensated with fluorine where the majority ofthe electron-hole pairs are generated. The short circuit current ofthe device is enhanced bythe combined effects of the back reflector 114 and the high conductivity ofthe improved wide band gap p amorphous silicon alloy ofthe invention.
Deposited on the intrinsic body 118 is a further doped layer 120 which is of opposite conductivity with respect to the first doped layer 116. It comprises an n+ conductivity amorphous silicon alloy. The n+ layer 120 is deposited from any of the gas mixtures previously referred toforthedeposition of such material. The n + layer 120 is deposited to a thickness between 50 and 500 angstroms and serves as a contact layer.
Atransparentconductiveoxide(TCO) layer 122 is then deposited overthe n+ layer 120. The TCO layer 122 can be deposited in a vapor deposition environment and, for example, may be indium tin oxide (ITO), cadmium stannate (Cd2SnO4), or doped tin oxide (SnO2).
On the surface of the TCO layer 122 is deposited a grid electrode 124 made of a metal having good electrical conductivity. The grid may comprise orthogonally related lines of conductive material occupying only a minor portion ofthe area ofthe metallic region, the rest of which is to be exposed to solar energy. For example, the grid 124 may occupy only aboutfrom 5to 10% ofthe entire area of the TCO layer 122. The grid electrode 124 uniformly collects current from theTCO layer 122 to assure a good low series resistanceforthe device.
To complete the device 110, an anti-reflection (AR) layer 126 is applied over the grid electrode 124 and the areas oftheTCO layer 122 between the grid electrode areas. The AR layer 126 has a solar radiation incident surface upon which impinges the solar radiation. For example, the AR layer 126 may have a thickness on the order of magnitude of the wavelength ofthe maximum energy pointofthe solar radiation spectrum, divided by four times the index of refraction of the anti-reflection layer 126. A suitable AR layer 126 would be zirconium oxide of about 500A in thickness with an index of refraction of 2.1.
The band gap of the intrinsic layer 118 may be adjusted for specific photoresponsive characteristics.
For example, one or more band gap decreasing elements such as germanium, tin, or lead may be incorporated into the intrinsic layer to decrease the band gap thereof (see for example U.S. Patent No.
4,342,044 issued in the names of Stanford R. Ovshins ky and Masatsugu Izu on July 1982 for Method for Optimizing Photo responsive Amorphous Alloys and Devices). This can be accomplished, for example, by introducing germane gase (GeH4) into the gas mixture from which the layer 118 is deposited.
Referring now to Fig. Sit illustrates another device 130 embodying the present invention.The device 130 is similar to the device of Fig. 3 except it does not include a back reflector and the p+ and n+ layers are reversed. The substrate 132 ofthe device 130 can be stainless steel for example. If desired, a reflecting layer can be deposited onto the substrate 132 by any ofthe processes previously referred to for such a layer and can be formed from silver, aluminum, or copper, for example.
Deposited on the substrate 132 is a first doped layer 134which, as illustrated, is of n+ conductivity. If desired, the n+ layer 134 may include a band gap increasing element such as nitrogen orcarbonto form a wide band gap n+ layer.
An intrinsic body 136 is deposited on the n+ layer 134 and, like the intrinsic body 118 of device 110, preferably includes an amorphous silicon-fluorine alloy of similarthickness.
Deposited on the intrinsic body 136 is a further doped layer 138 which is opposite in conductivity with respectto thefirst doped layer 134 and preferably is a wide band gap p+ layer incorporating oxygen in accordance with the present invention.
The device is completed bytheforming of a TCO layer 140 over the p+ layer 138, a grid electrode 142.
These steps can be accomplished in a manner as described with respect to the device 110 of Fig. 4.
As in the case ofthe previous embodiment, the band gap ofthe intrinsic layer 136 can be adjusted for a particular photoresponse characteristic with the incorporation of band gap decreasing elements. As a further alternative, the band gap of the intrinsic body 136 can be gradedso asto be gradually increasing from the n+ layer 134to thefurther p+ layer 138 (see for example co-pending U.S. Application Serial No.
427,756 filed in the names of Stanford R. Ovshinsky and David Adler on September 29,1 982 for Methods for Grading the Band Gaps of Amorphous Alloys and Devices). For example, as the intrinsic layer 136 is deposited, one or more band gap decreasing elements such as germanium, tin, or lead can be incorporated in the alloys in gradually decreasing concentration. Germane gas (GeH4) forexample can be introduced into the glow discharge deposition chamberfrom a relatively high concentration at first and gradually diminished thereafter as the intrinsic layer is deposited to a point where such introduction is terminated. The resulting intrinsic body will thus have a band gap decreasing element, such as germanium, therein in gradually decreasing concentrations from the n+ layer 134 towards the p+ layer 138.
Referring now to Fig. 6, a multiple cell device 150 is there illustrated in sectional view which is arranged in tandem configuration. The device 150 comprises two single cell units 152 and 154 arranged in series relation which embody the present invention. As can be appreciated, plural single cell units of more than two can be utilized.
The device 150 includes a substrate 156 formed from a metal having good electrical conductivity such as stainless steel or aluminum, for example. Deposited on the substrate 156 is a back reflector 157 which may be formed as previously described. The first cell unit 152 includes a first doped p+ amorphous silicon alloy layer 158 deposited on the back reflector 157. The p+ layer is preferably a wide band gap p amorphous silicon alloy in accordance with the present invention. It can be deposited from any of the previously mentioned starting materials for depositing such material.
Deposited on the wide band gap p+ layer 158 is a first intrinsic amorphous silicon alloy body 160. The first intrinsic alloy body 160 is preferably an amorphous silicon-fluorine alloy.
Deposited on the intrinsic layer 160 is afurther doped amorphous silicon alloy layer 162. It is opposite in conductivity with the respect to the conductivity ofthefirst doped layer 158 and thus is an n+ layer.
The second unit cell 154 is essentially identical and includes a first doped p+ layer 164, an intrinsic body 166 and afurtherdopedn+ layer 168. The device 150 is completed with a TCO layer 170, a grid electrode 172, and an antireflection layer 174.
The band gaps of the intrinsic layers are preferably adjusted so thatthe band gap of layer 166 is greater than the band gap of layer 160. To that end, the alloy forming layer 166 can include one or more band gap increasing elements such as nitrogen and carbon.
The intrinsic alloy forming the intrinsic layer 160 can include one or more band gap decreasing elements such as germanium, tin, or lead.
It can be noted from the figure that the intrinsic layer 160 ofthe cell is thickerthan the intrinsic layer 166. This allows the entire usable spectrum of the solar energy to be utilized for generating electronhole pairs.
Although a tandem cell embodiment has been shown and described herein, the unit cells can also be isolated from one another with oxide layers for exampletoform a stacked multiplecell. Each cell could include a pairofcollection electrodes to facilitate the series connection of the cells with external wiring.
As a further alternative, and as mentioned with respect to the single cells previously described, one or more of the intrinsic bodies of the unitcellscan include alloys having graded band gaps. Anyone or more ofthe band gap increasing ordecreasing elements previously mentioned can be incorporated into the intrinsic alloys for this purpose. Reference may also be made to co-pending U.S. Application Serial No.427,757 filed in the names of Stanford R.
Ovshinsky and David Adler on September29, 1982for Multiple Cell Photoresponsive Amorphous Alloys and Devices.
For each embodiment of the invention described herein, the alloy layers otherthan the intrinsic alloy layers can be otherthan amorphous layers, such as polycrystalline layers. (By the term "amorphous" is meant an alloy or material which has long range disorder, although it may have short or intermediate order or even contain attimes some crystalline inclusions.) Preferred embodiments of the present invention provide wide band gap p-type amorphous silicon alloys exhibiting conductivities substantially greater than the heretofore mentioned conventional wide band gap p-type amorphous silicon alloyfora given band gap.
At least one amorphous silicon alloy layer of the devices is a wide band gap p-type amorphous silicon alloy layer having improved electrical conductivity.
One advantage of this approach is that increased absorption in the active layers is possible while providing increased current collection efficiency to facilitate increased short circuit currents. Another advantage is that the improved photoresponsive characteristics offluorinated amorphous silicon alloys can be morefully realized in photocoltaic devices by practicing the present invention. The invention has its most important application in making improved amorphous silicon alloy photovoltaic devices ofthe p-i-n configuration, either as single cells or multiple cells comprising a plurality of single cell units.

Claims (52)

1. A method of making a wide band gap p amorphous silicon alloy, said method comprising depositing on a substrate a material including at least silicon, incorporating in said material at least one density of states reducing element and a p-type dopant, and introducing a band gap increasing element into said material, said band gap increasing element being oxygen, to produce a p-type amorphous silicon alloy including oxygen in the range of one to thirty atomic percent.
2. The method according to claim 1 wherein said at least one density of states reducing element is hydrogen.
3. The method according to claim 1 wherein said at least one density of states reducing element is fluorine.
4. The method according to claim 3further including introducing a second density of states reducing element, said second element being hydrogen.
5. The method according to claim 4wherein both said density of states reducing elements are incorporated into said deposited alloy substantially simul taneouslywith the oxygen.
6. The method according to any one of claims 1 to 5 wherein said p-type dopant is boron.
7. The method according to any one of claims 1 to 6 wherein said alloy is glow discharge deposited from at least a mixture of SiH4, B2H6, and oxygen.
8. The method according to claim 7 wherein the concentration of oxygen in said mixture is in the range of .01 to 1 volume percent.
9. The method according to claim 8wherein said oxygen is diluted in said mixture with argon gas.
10. The method according to any one of claims 7 to 9 wherein said mixture comprises about 94.6 volume percent SiH4, about 5.2 volume percent B2H6, and about .2volume percent oxygen.
11. The method according to any one of claims 1 to 6 wherein said alloy is glow discharge deposited from at least a mixture of SiF4, SiH4, B2Hs, and oxygen.
12. The method according to claim 11 wherein the concentration of oxygen in said mixture is in the range of .01 to 1 volume percent.
13. Themethod accordingtoclaim 12wherein said oxygen is diluted in said mixture with argon gas.
14. The method accordingto any one of claims 1 to 13 fu rther including incorporating a second band gap increasing element in minor amounts compared to the amount of incorporation of said oxygen, said second band gap increasing element being carbon.
15. An amorphous alloy made bythe process according to claim 1.
16. An amorphous alloy made bythe process according to claim 2.
17. An amorphous alloy made bythe process according to claim 3.
18. An amorphousalloymadebythe process according to claim 4.
19. An amorphous alloy made bythe process according to claim 6.
20. An amorphous alloy made bythe process according to claim 14.
21. Awide band gap p amorphous silicon alloy, said alloy including silicon and incorporating at least one density of states reducing element and a p-type dopanttherein, the alloyfurther including at least one band gap increasing element incorporated therein, said band gap increasing element being oxygen, and said alloy including said oxygen in the range of one to thirty atomic percent.
22. The alloy according to claim 21 wherein said at least one density of states reducing element is hydrogen.
23. The alloy according to claim 21 wherein said at least one density of states reducing element is fluorine.
24. The alloy according to claim 23furtherinclud ing a second density of states reducing element incorporated therein, said element being hydrogen.
25. The alloy according to any one of claims 21 to 24 wherein said p-type dopant is boron.
26. The alloy according to any one of claims 21 to 25 further including a second band gap increasing element in minorconcentration compared to the concentration of said oxygen, said second band gap increasing element being carbon.
27. A photoresponsive device of the type comprising superimposed layers of various materials including an amorphous semiconductor alloy body Forming an intrinsic active photoresponsive layer upon which radiation can impinge to produce charge carriers, the device including a wide band gap p amorphous silicon alloy layer adjacent said intrinsic layer including at least one density of states reducing element, a p-type dopant, and at least one band gap increasing element, said band gap increasing element being oxygen, said wide band gap p amorphous silicon alloy including said oxygen in the range of one to thirty atomic percent.
28. The device according to claim 27 further including an n-type amorphous silicon alloy layer adjacent said intrinsic layer on the side thereof opposite said wide band gap p amorphous silicon alloy layer.
29. The deviceaccording to claim 28further including a back reflecting layer adjacent said wide band gap p amorphous silicon alloy layer on the side thereof opposite said intrinsic layer.
30. The device according to claim 28 further including a back reflecting layer adjacent said n-type amorphous silicon alloy layer on the side thereof opposite said intrinsic layer.
31. The device according to any one of claims 27 to 30 wherein said density of states reducing element is hydrogen.
32. The device according to any one of claims 27 to 30 wherein said density of states reducing element is fluorine.
33. The device according to claim 32 wherein said wide band gap p amorphous silicon alloy layer further includes a second density of states reducing element, said second density of states reducing element being hydrogen.
34. The device according to any one of claims 27 to 33 wherein said p-type dopantis boron.
35. The device according to any one of claims 27 to 34wherein said wide band gap p amorphous silicon alloy layerfurther includes a second band gap increasing element in minor concentrations com pared to the concentration of said oxygen, said second band gap increasing element being carbon.
36. A multiple cell photovoltaic device formed from multiple layers of amorphous semiconductor alloys deposited on a substrate, said device com prising: a plurality of single cell units arranged in series relation, each said single cell unitcomprising afirst doped amorphous semiconductor alloy layer, a body of intrinsic amorphous semiconductor alloy depo sited on said first doped layer, a further doped amorphous semiconductor alloy layer deposited on said intrinsic body and being of opposite conductivity with respect to said first doped amorphous semicon ductor alloy layer, and wherein at least one of said doped amorphous semiconductor alloy layers of at least one of said single cell units comprises a wide band gap p amorphous silicon alloy including at least one density of states reducing element, a p-type dopant, and at least one band gap increasing element, said band gap increasing element being oxygen, and said wide band gap p amorphous silicon alloy including said oxygen in the range of one to thirty atomic percent
37. The deviceaccording to claim 36wherein said wide band gap p amorphous silicon alloy includes a second band gap increasing element in minor concentrations compared to the concentration of said oxygen, said second band gap increasing element being carbon.
38. Adevice according to any one of claims 36 or 37 wherein said density of states reducing element is hydrogen.
39. A device according to any one of claims 36 or 37 wherein said density of states reducing element is fluorine.
40. A device according to claim 39 wherein said wide band gap p amorphous silicon alloy includes a second density of states reducing element, said second density of states reducing element being hydrogen.
41. A device according to any one of claims 36 to 40 further including a back reflecting layer immediately adjacent said substrate.
42. A device according to claim 41 wherein said wide band gap p amorphous silicon alloy layer is adjacent said back reflecting layer on the side thereof opposite said substrate.
43. A device according to claim 41 wherein said wide band gap p amorphous silicon alloy layer forms thetop most amorphous semiconductor alloy layer with respect to said substrate.
44. A device according to any one of claims 36 to 43 wherein each said intrinsic body has a band gap and wherein at leastone said intrinsic body has a band gap adjusted for a specific photoresponse wavelength characteristic.
45. A device according to claim 44 wherein said at least one intrinsic body has a decreased band gap.
46. A deviceaccording to claim 45 wherein said at least one intrinsic body includes at least one band gap decreasing element therein selected from the group of germanium, tin, or lead.
47. A device according to claim 44 wherein said at least one intrinsic body has an increased band gap.
48. A device according to claim 47 wherein said at least one intrinsic body includes at least one band gap increasing element therein selected from the group of carbon and nitrogen.
49. A method of making a wide band gap p amorphous silicon alloy substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 3 when taken in conjunction with any one of Fig ures 4,5 or 6.
50. A multiple cell photovoltaic device substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 3 when taken in conjunction with any one of Figures 4,5 or 6.
51. A photoresponsive device substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 3when taken in conjunction with any one of Figures 4,5 or 6.
52. Awide band gap p amorphous silicon alloy as claimed in Claim 21 substantially as hereinbefore described.
GB08311175A 1982-04-28 1983-04-25 Amorphous semiconductor materials Withdrawn GB2124826A (en)

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Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2007021A (en) * 1977-10-12 1979-05-10 Energy Conversion Devices Inc High temperature amorphous semiconductor member and method of making it
GB2017405A (en) * 1978-03-22 1979-10-03 Energy Conversion Devices Inc Amorphous semiconductors
EP0035146A2 (en) * 1980-02-15 1981-09-09 Matsushita Electric Industrial Co., Ltd. Semiconductor photoelectric device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2007021A (en) * 1977-10-12 1979-05-10 Energy Conversion Devices Inc High temperature amorphous semiconductor member and method of making it
GB2017405A (en) * 1978-03-22 1979-10-03 Energy Conversion Devices Inc Amorphous semiconductors
EP0035146A2 (en) * 1980-02-15 1981-09-09 Matsushita Electric Industrial Co., Ltd. Semiconductor photoelectric device

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GB8311175D0 (en) 1983-06-02
IT8320731A0 (en) 1983-04-21
AU1368883A (en) 1983-11-03
JPS58199710A (en) 1983-11-21
NL8301440A (en) 1983-11-16
DE3314197A1 (en) 1983-11-03
FR2526223A1 (en) 1983-11-04

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