Patent US5019177A successfully refreshed from Google Patents.
US5019177A
Expired / Lapsed
US
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Monolithic tandem solar cell
Assignee: United States Department of Energy
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Filing: 1989-11-03
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Granted: 1991-05-28
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Expires: 2009-11-03
Abstract
Abstract A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, and (c) a second photoactive subcell on the first subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched. The solar cell can be provided as a two-terminal device or a three-terminal device.
Inventors
- 👤 Mark W. Wanlass
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:38
CPC Classifications
H; H10; H10F; H10F10/00; H10F10/10; H10F10/14; H10F10/142; H10F19/00; H10F19/20; H10F19/40; H10F71/00; H10F71/127; H10F71/1272; H10F77/00; H10F77/10; H10F77/12; H10F77/124; H10F77/1248; H10F77/40; H10F77/42; H10F77/488; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/52; Y02E10/544; Y02E10/547; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
91 words
A single-crystal, monolithic, tandem, photovoltaic solar cell, comprising: (a) an InP substrate having upper and lower surfaces; (b) a first photoactive subcell on said upper surface of said substrate; said first subcell comprising Ga 0 .47 In 0 .53 As; said first subcell including a homojunction; and (c) a second photoactive subcell on said first photoactive subcell; wherein said second subcell comprises InP; said second subcell including a homojunction; wherein said GaInAs is lattic-matched with said InP; and wherein said second subcell has a larger energy bandgap than said first subcell.
Claim 2
Dependent Claim
91 words
A single-crystal, monolithic, tandem, photovoltaic solar cell, comprising: (a) an InP substrate having upper and lower surfaces; (b) a first photoactive subcell on said upper surface of said substrate; said first subcell comprising Ga 0 .47 In 0 .53 As; said first subcell including a homojunction; and (c) a second photoactive subcell on said first photoactive subcell; wherein said second subcell comprises InP; said second subcell including a homojunction; wherein said GaInAs is lattic-matched with said InP; and wherein said second subcell has a larger energy bandgap than said first subcell.
Claim 3
Dependent Claim
20 words
A photovoltaic solar cell in accordance with claim 1, wherein said first and second subcells each include an n/p homojunction.
Claim 4
Dependent Claim
25 words
A photovoltaic solar cell in accordance with claim 2, wherein said solar cell includes two output terminals, and wherein said subcells are connected in series.
Claim 5
Dependent Claim
20 words
A photovoltaic solar cell in accordance with claim 3, wherein said subcells are interconnected by means of a tunnel junction.
Claim 6
Dependent Claim
21 words
A photovoltaic solar cell in accordance with claim 3, wherein said subcells are electrically connected by means of a metal interconnect.
Claim 7
Dependent Claim
36 words
A photovoltaic solar cell in accordance with claim 1, wherein one of said subcells includes an n/p homojunction and the other said subcell includes a p/n homojunction; and wherein said solar cell includes three output terminals.
Claim 8
Dependent Claim
94 words
A single-crystal, monolithic, tandem, photovoltaic solar cell, comprising: (a) an InP substrate having upper and lower surfaces; (b) a first photoactive subcell on said upper surface of said substrate; said first subcell comprising GaInAs and including a homojunction; wherein said GaInAs is of the composition Ga 0 .47 In 0 .53 As; and (c) a second photoactive subcell on said first subcell wherein said second subcell comprises InP and includes a homojunction; wherein said GaInAs is lattice-matched with said InP; and wherein said second subcell has a larger energy bandgap than said first subcell.
Claim 9
Dependent Claim
94 words
A single-crystal, monolithic, tandem, photovoltaic solar cell, comprising: (a) an InP substrate having upper and lower surfaces; (b) a first photoactive subcell on said upper surface of said substrate; said first subcell comprising GaInAs and including a homojunction; wherein said GaInAs is of the composition Ga 0 .47 In 0 .53 As; and (c) a second photoactive subcell on said first subcell wherein said second subcell comprises InP and includes a homojunction; wherein said GaInAs is lattice-matched with said InP; and wherein said second subcell has a larger energy bandgap than said first subcell.
Claim 10
Dependent Claim
120 words
A photovoltaic solar cell in accordance with claim 7, wherein said second subcell includes an upper surface; wherein each said subcell includes a photoactive region; and wherein said second subcell includes a lower region below its said photoactive region; wherein said lower region of said second subcell and the adjacent upper region of said first subcell are of common conductivity type; said solar cell further comprising: (a) a conductive layer providing low resistance ohmic contact to said lower surface of said InP substrate; (b) a conductive top contact providing low resistance ohmic contact with said upper surface of said second subcell; and (c) a conductive middle contact providing low resistance ohmic contact with said lower region of said second subcell.
Claim 11
Independent Claim
121 words
A method for preparing a single crystal, monolithic, tandem, photovoltaic solar cell, comprising the steps of: (a) providing an InP substrate having an upper surface; (b) epitaxially depositing on said upper surface of layer of GaInAs to form a first photoactive subcell; wherein said GaInAs is deposited in a manner such that a homojunction is provided in said layer; wherein said GaInAs is of the composition Ga 0 .47 In 0 .53 As; (c) epitaxially depositing a layer of InP on said GaInAs layer to form a second photoactive subcell; wherein said InP is deposited in a manner such that a homojunction is provided in said InP layer; wherein said GaInAs is lattice-matched with said InP substrate and said InP layer.
Claim 12
Independent Claim
121 words
A method for preparing a single crystal, monolithic, tandem, photovoltaic solar cell, comprising the steps of: (a) providing an InP substrate having an upper surface; (b) epitaxially depositing on said upper surface of layer of GaInAs to form a first photoactive subcell; wherein said GaInAs is deposited in a manner such that a homojunction is provided in said layer; wherein said GaInAs is of the composition Ga 0 .47 In 0 .53 As; (c) epitaxially depositing a layer of InP on said GaInAs layer to form a second photoactive subcell; wherein said InP is deposited in a manner such that a homojunction is provided in said InP layer; wherein said GaInAs is lattice-matched with said InP substrate and said InP layer.
Claim 13
Dependent Claim
15 words
A method in accordance with claim 9, wherein each said homojunction is an n/p type.
Claim 14
Dependent Claim
23 words
A method in accordance with claim 10, wherein said solar cell includes two output terminals, and wherein said subcells are connected in series.
Claim 15
Dependent Claim
34 words
A method in accordance with claim 9, wherein one of said subcells includes an n/p homojunction and the other of said subcells includes a p/n homojunction; wherein said solar cell includes three output terminals.
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| 7.5 Years (Year 8) | 1998-05-27 | 1998-11-26 | 1999-05-28 | $3760.00 | Window Closed / Lapsed |
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