US5571339A
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Hydrogen passivated heteroepitaxial III-V photovoltaic devices grown on lattice-mismatched substrates, and process
Assignee: Essential Research Inc
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Filing: 1995-04-17
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Granted: 1996-11-05
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Expires: 2015-04-17
Abstract
Abstract A hydrogen passivated photovoltaic device such as a solar cell comprises a lattice mismatched substrate such as Ge or Si, and a hydrogen passivated heteroepitaxial layer such as InP grown on the substrate. The hydrogen passivated heteroepitaxial III-V photovoltaic device is produced by exposing a sample of a heteroepitaxial III-V material grown on a lattice-mismatched substrate to reactive hydrogen species at elevated temperatures. Reactive hydrogen forms bonds with dangling bonds along dislocations defined in the sample. The electrical activity in the dislocations is passivated as a result of the hydrogenation process.
Inventors
- 👤 Steven A. Ringel
- 👤 Richard W. Hoffman, Jr.
- 👤 Basab Chatterjee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:11
CPC Classifications
H; H10; H10F; H10F71/00; H10F71/128; H10F71/127; H10F71/1276; H10F71/129; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/544; Y02E10/547; Y02P; Y02P70/00; Y02P70/50; Y10; Y10S; Y10S438/00; Y10S438/933
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
22 words
A photovoltaic device, comprising: a lattice-mismatched substrate; and a hydrogen-plasma-passivated heteroepitaxial layer formed of a III-V semiconductor material grown on said substrate.
Claim 2
Dependent Claim
22 words
A photovoltaic device, comprising: a lattice-mismatched substrate; and a hydrogen-plasma-passivated heteroepitaxial layer formed of a III-V semiconductor material grown on said substrate.
Claim 3
Dependent Claim
18 words
A photovoltaic device, as set forth in claim 1, wherein the lattice-mismatched substrate comprises a group IV material.
Claim 4
Dependent Claim
15 words
A photovoltaic device, as set forth in claim 2, wherein the lattice-mismatched substrate comprises Si.
Claim 5
Dependent Claim
15 words
A photovoltaic device, as set forth in claim 2, wherein the lattice-mismatched substrate comprises Ge.
Claim 6
Dependent Claim
15 words
A photovoltaic device, as set forth in claim 1, wherein the lattice-mismatched substrate comprises GaAs.
Claim 7
Dependent Claim
16 words
A photovoltaic device, as set forth in claim 1, wherein the hydrogen-passivated heteroepitaxial layer comprises InP.
Claim 8
Dependent Claim
16 words
A photovoltaic device, as set forth in claim 1, wherein the hydrogen-passivated heteroepitaxial layer comprises InGaAs.
Claim 9
Dependent Claim
23 words
A photovoltaic devices as set forth in claim 1, wherein the heteroepitaxial layer defines dislocations which have been electrically passivated by plasma hydrogenation.
Claim 10
Dependent Claim
17 words
A photovoltaic device, as set forth in claim 1, wherein the photovoltaic device is a solar cell.
Claim 11
Dependent Claim
32 words
A photovoltaic cell comprising: a lattice-mismatched group IV substrate including an element selected from the group consisting of Ge and Si; and a hydrogen-passivated heteroeptiaxial layer of InP grown on the substrate.
Claim 12
Dependent Claim
32 words
A photovoltaic cell comprising: a lattice-mismatched group IV substrate including an element selected from the group consisting of Ge and Si; and a hydrogen-passivated heteroeptiaxial layer of InP grown on the substrate.
Claim 13
Dependent Claim
96 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, comprising the steps of: growing a III-V heteroepitaxial material on a lattice mismatched substrate; exposing the heteroepitaxial III-V material grown on the lattice mismatched substrate to a plasma of hydrogen at an elevated temperature sufficient to cause diffusion of reactive hydrogen ions into the heteroepitaxial III-V material; bonding the reactive hydrogen to dangling bonds along dislocations defined in the heteroepitaxial material; reducing electrical activity in the dislocations by hydrogenation; producing a hydrogen passivated heteroepitaxial III-V photovoltaic device; and reactivating any dopants inadvertently passivated by the hydrogen.
Claim 14
Dependent Claim
96 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, comprising the steps of: growing a III-V heteroepitaxial material on a lattice mismatched substrate; exposing the heteroepitaxial III-V material grown on the lattice mismatched substrate to a plasma of hydrogen at an elevated temperature sufficient to cause diffusion of reactive hydrogen ions into the heteroepitaxial III-V material; bonding the reactive hydrogen to dangling bonds along dislocations defined in the heteroepitaxial material; reducing electrical activity in the dislocations by hydrogenation; producing a hydrogen passivated heteroepitaxial III-V photovoltaic device; and reactivating any dopants inadvertently passivated by the hydrogen.
Claim 15
Dependent Claim
38 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 11, comprising the additional step of: capping the heteroepitaxial material with a thin hydrogen permeable nitride layer prior to the step of exposing.
Claim 16
Dependent Claim
25 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 12, comprising the additional step of: removing the nitride layer.
Claim 17
Dependent Claim
22 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 11, wherein the heteroepitaxial material comprises InP.
Claim 18
Dependent Claim
27 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 11, wherein the heteroepitaxial material comprises InGaAs and the substrate comprises InP.
Claim 19
Dependent Claim
24 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 11, wherein the substrate comprises a group IV element.
Claim 20
Dependent Claim
21 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 16, wherein the substrate comprises Si.
Claim 21
Dependent Claim
21 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 16, wherein the substrate comprises Ge.
Claim 22
Dependent Claim
21 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 11, wherein the substrate is GaAs.
Claim 23
Dependent Claim
39 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 11, wherein the step of reactivating comprises heating a cooled hydrogen passivated heteroepitaxial III-V photovoltaic device to a temperature sufficient to reactivate the dopants.
Claim 24
Dependent Claim
48 words
In a photovoltaic device comprising a lattice mismatched substrate and a III-V heteroepitaxial material grown on said substrate, the heteroepitaxial material defining electrically active dislocations therein, the improvement comprising: plasma-formed hydrogen bonds in the dislocations defined within the heteroepitaxial material wherein electrical activity in the dislocations is reduced.
Claim 25
Dependent Claim
48 words
In a photovoltaic device comprising a lattice mismatched substrate and a III-V heteroepitaxial material grown on said substrate, the heteroepitaxial material defining electrically active dislocations therein, the improvement comprising: plasma-formed hydrogen bonds in the dislocations defined within the heteroepitaxial material wherein electrical activity in the dislocations is reduced.
Claim 26
Dependent Claim
63 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, comprising the steps of: growing heteroepitaxial InP on a lattice mismatched substrate; diffusing reactive hydrogen ions from a plasma deep into dislocations defined within the bulk of the heteroepitaxial InP; passivating the dislocations by bonding the reactive hydrogen to dangling bonds in the dislocations; and reactivating any dopants inadvertently passivated by the hydrogen.
Claim 27
Dependent Claim
63 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, comprising the steps of: growing heteroepitaxial InP on a lattice mismatched substrate; diffusing reactive hydrogen ions from a plasma deep into dislocations defined within the bulk of the heteroepitaxial InP; passivating the dislocations by bonding the reactive hydrogen to dangling bonds in the dislocations; and reactivating any dopants inadvertently passivated by the hydrogen.
Claim 28
Dependent Claim
29 words
A process for preparing a hydrogen passivated heteroepitaxial photovoltaic device, as set forth in claim 22, wherein the heteroepitaxial InP is grown to at least 2 microns in thickness.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1999-11-05 | 2000-05-06 | 2000-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-11-05 | 2004-05-06 | 2004-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-11-05 | 2008-05-06 | 2008-11-05 | $7700.00 | Window Closed / Lapsed |