Patent US4239553A successfully refreshed from Google Patents.
US4239553A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin film photovoltaic cells having increased durability and operating life and method for making same
Assignee: University of Delaware
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Filing: 1979-05-29
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Granted: 1980-12-16
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Expires: 1999-05-29
Abstract
Abstract A solar cell having a copper-bearing absorber is provided with a composite transparent encapsulating layer specifically designed to prevent oxidation of the copper sulfide. In a preferred embodiment, the absorber is a layer of copper sulfide and the composite layer comprises a thin layer of copper oxide formed on the copper sulfide and a layer of encapsulating glass formed on the oxide. It is anticipated that such devices, when exposed to normal operating conditions of various terrestrial applications, can be maintained at energy conversion efficiencies greater than one-half the original conversion efficiency for periods as long as thirty years.
Inventors
- 👤 Allen M. Barnett
- 👤 James V. Masi
- 👤 Robert B. Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:31
CPC Classifications
H; H10; H10F; H10F10/00; H10F10/10; H10F10/16; H10F10/169; H10F19/00; H10F19/80; H10F71/00; Y; Y02; Y02E; Y02E10/00; Y02E10/50
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
213 words
In a photovoltaic device of the type comprising a first electrical contact means, a layer of absorber material in ohmic electrical contact with said first electrical contact means, transparent encapsulation means overlying said first electrical contact means and said absorber a layer of collector material in rectifying electrical contact with said absorber and forming a junction therewith, and a second electrical contact means in ohmic electrical contact with said collector, the improvement being said encapsulant means comprises a composite layer of a barrier member and an overlying thin layer of glass, said barrier member having a thickness between 100 and 10,000 angstroms, said glass being bonded directly to said barrier member, said barrier member being made of a material which is chemically and electrically compatible with the material of said absorber, and said barrier member material being capable of minimizing passage of oxygen and of bonding glass and of reducing the tendency of glass to crack and microfissure thereby facilitating bonding said layer of glass to the remainder of said device and minimizing the occurrence of cracks and microfissures in said layer of glass and minimizing the passage of oxygen and moisture and air through any cracks or microfissures in said layer of glass to preserve the stoichiometry of said underlying, absorber material.
Claim 2
Dependent Claim
213 words
In a photovoltaic device of the type comprising a first electrical contact means, a layer of absorber material in ohmic electrical contact with said first electrical contact means, transparent encapsulation means overlying said first electrical contact means and said absorber a layer of collector material in rectifying electrical contact with said absorber and forming a junction therewith, and a second electrical contact means in ohmic electrical contact with said collector, the improvement being said encapsulant means comprises a composite layer of a barrier member and an overlying thin layer of glass, said barrier member having a thickness between 100 and 10,000 angstroms, said glass being bonded directly to said barrier member, said barrier member being made of a material which is chemically and electrically compatible with the material of said absorber, and said barrier member material being capable of minimizing passage of oxygen and of bonding glass and of reducing the tendency of glass to crack and microfissure thereby facilitating bonding said layer of glass to the remainder of said device and minimizing the occurrence of cracks and microfissures in said layer of glass and minimizing the passage of oxygen and moisture and air through any cracks or microfissures in said layer of glass to preserve the stoichiometry of said underlying, absorber material.
Claim 3
Dependent Claim
26 words
An improved photovoltaic cell according to claim 1 wherein said barrier member is a layer of copper oxide, and said absorber is a copper bearing material.
Claim 4
Dependent Claim
30 words
An improved photovoltaic device according to claim 2 wherein said absorber is a copper-bearing material selected from the group consisting of copper sulfide, copper indium sulfide and copper indium selenide.
Claim 5
Dependent Claim
32 words
An improved photovoltaic cell according to claim 2 wherein said absorber comprises copper sulfide and said collector comprises a material selected from the group consisting of cadmium sulfide and zinc cadmium sulfide.
Claim 6
Dependent Claim
29 words
An improved photovoltaic cell according to claim 2 wherein said glass is alumino-borosilicate glass having a thickness in excess of about 1 micron and less than about 30 microns.
Claim 7
Dependent Claim
20 words
An improved photovoltaic cell according to claim 1 wherein the cell is a cadmium sulfide/copper sulfide front wall type cell.
Claim 8
Dependent Claim
36 words
An improved photovoltaic cell according to claim 1 wherein said first electrical contact means is a transparent electrical contact in grid form, and said barrier member is located between said absorber and said transparent electrical contact.
Claim 9
Dependent Claim
29 words
An improved photovoltaic cell according to claim 1 wherein said first electrical contact is a transparent electrical contact in grid form disposed between said absorber and said barrier member.
Claim 10
Dependent Claim
190 words
In a method for fabricating a photovoltaic device comprising the steps of providing a first electrical contact, depositing a layer of collector material on said first electrical contact, depositing a layer of absorber material on said collector to form a junction therebetween, and applying a second electrical contact and transparent encapsulation means to said absorber, the improvement being: applying the encapsulation means by the steps of depositing on said absorber a composite layer of a barrier member having a thickness between 100 and 10,000 angstroms and an overlying thin layer of glass, selecting as said barrier member a material which is chemically and electrically compatible with the material of said absorber and which functions to minimize the occurrence of cracks and microfissures in said layer of glass and further to minimize the passage of oxygen and moisture and air through any cracks or microfissures in said layer of glass to thereby preserve the stoichiometry of said underlying absorber material, and depositing said layer of glass directly on said barrier member with said barrier member functioning to facilitate the bonding of said layer of glass to the rest of said device.
Claim 11
Dependent Claim
190 words
In a method for fabricating a photovoltaic device comprising the steps of providing a first electrical contact, depositing a layer of collector material on said first electrical contact, depositing a layer of absorber material on said collector to form a junction therebetween, and applying a second electrical contact and transparent encapsulation means to said absorber, the improvement being: applying the encapsulation means by the steps of depositing on said absorber a composite layer of a barrier member having a thickness between 100 and 10,000 angstroms and an overlying thin layer of glass, selecting as said barrier member a material which is chemically and electrically compatible with the material of said absorber and which functions to minimize the occurrence of cracks and microfissures in said layer of glass and further to minimize the passage of oxygen and moisture and air through any cracks or microfissures in said layer of glass to thereby preserve the stoichiometry of said underlying absorber material, and depositing said layer of glass directly on said barrier member with said barrier member functioning to facilitate the bonding of said layer of glass to the rest of said device.
Claim 12
Dependent Claim
39 words
The improved method of claim 9 wherein copper oxide is selected as said barrier member material, and said glass layer is alumino-borosilicate glass deposited to a thickness in excess of about 1 micron and less than about 30 microns.
Claim 13
Dependent Claim
26 words
The improved method of claim 10 further including the step of heating said absorber in a reducing atmosphere prior to depositing said layer of copper oxide.
Claim 14
Dependent Claim
26 words
The improved method of claim 10 wherein said absorber is deposited on said collector by depositing a layer of a copper-bearing absorber material on said collector.
Claim 15
Dependent Claim
19 words
The improved method of claim 9 wherein said composite layer is deposited after the absorber stoichiometry has been optimized.
Claim 16
Dependent Claim
15 words
The improved method of claim 9 wherein said barrier member is deposited by vacuum evaporation.
Claim 17
Dependent Claim
14 words
The improved method of claim 9 wherein said barrier member is deposited by sputtering.
References Cited (Backward Citations)
US3888697A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-16 | 1984-06-16 | 1984-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-16 | 1988-06-16 | 1988-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-16 | 1992-06-16 | 1992-12-16 | $7700.00 | Window Closed / Lapsed |