US5009719A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tandem solar cell
Assignee: Mitsubishi Electric Corp
•
Filing: 1989-11-08
•
Granted: 1991-04-23
•
Expires: 2009-11-08
Abstract
Abstract A tandem solar cell device includes an upper solar cell, a lower solar cell, and an intervening buffer layer. A short wavelength region of the incident light is absorbed by the upper solar cell while the light having passed through the upper solar cell is absorbed by the lower solar cell. The buffer layer is a semiconductor layer having a larger band gap energy than the upper solar cell, a crystalline lattice match with the upper solar cell, and a tunnel junction.
Inventors
- 👤 Susumu Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:21
CPC Classifications
H; H10; H10F; H10F10/00; H10F10/10; H10F10/14; H10F10/142; H10F71/00; H10F71/125; H10F71/1257; H10F77/00; H10F77/20; H10F77/206; H10F77/211; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/544; Y02E10/547
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
171 words
A tandem solar cell including: an upper solar cell for converting relatively short wavelength incident light into electricity, comprising a first crystalline semiconductor having a first lattice constant and first energy band gap; an intermediate solar cell for converting relatively long wavelength incident light that has passed through said upper solar cell into electricity, comprising a second crystalline semiconductor having a second energy band gap smaller than the first energy band gap; a lower solar cell for converting relatively long wavelength incident light that has passed through said intermediate solar cell into electricity, comprising a third crystalline semiconductor having a third energy band gap smaller than the second energy band gap; and crystalline semiconductor buffer layers respectively disposed between said upper and intermediate solar cells and between said intermediate and lower solar cells, each buffer layer having an energy band gap larger than the first energy band gap and a lattice constant approximately the same as the first lattice constant and including a tunneling junction within each of said buffer layers.
Claim 2
Dependent Claim
171 words
A tandem solar cell including: an upper solar cell for converting relatively short wavelength incident light into electricity, comprising a first crystalline semiconductor having a first lattice constant and first energy band gap; an intermediate solar cell for converting relatively long wavelength incident light that has passed through said upper solar cell into electricity, comprising a second crystalline semiconductor having a second energy band gap smaller than the first energy band gap; a lower solar cell for converting relatively long wavelength incident light that has passed through said intermediate solar cell into electricity, comprising a third crystalline semiconductor having a third energy band gap smaller than the second energy band gap; and crystalline semiconductor buffer layers respectively disposed between said upper and intermediate solar cells and between said intermediate and lower solar cells, each buffer layer having an energy band gap larger than the first energy band gap and a lattice constant approximately the same as the first lattice constant and including a tunneling junction within each of said buffer layers.
Claim 3
Dependent Claim
30 words
The tandem solar cell of claim 1 wherein said lower solar cell comprises silicon and said intermediate and upper solar cells comprises a III-V compound semiconductor including Ga and As.
Claim 4
Dependent Claim
18 words
The tandem solar cell of claim 2 wherein said upper solar cell comprises Al x Ga 1-x As.
Claim 5
Dependent Claim
35 words
The tandem solar cell of claim 2 including a window layer comprising an Al x Ga 1-x As layer, where x is 0.8 to 0.9, disposed on said upper solar cell for receiving incident light.
Claim 6
Dependent Claim
17 words
The tandem solar cell of claim 1 wherein at least one of said buffer layers comprises ZnSe.
Claim 7
Dependent Claim
21 words
The tandem solar cell of claim 1 wherein at least one of said buffer layers comprises Al x Ga 1-x As.
Claim 8
Dependent Claim
21 words
The tandem solar cell of claim 1 including an anti-reflection film disposed on said upper solar cell for receiving incident light.
Claim 9
Dependent Claim
32 words
The tandem solar cell of claim 1 wherein said intermediate solar cell comprises GaAs and said upper solar cell comprises AlGaAs for receiving and transmitting incident light to said intermediate solar cell.
Claim 10
Dependent Claim
32 words
The tandem solar cell of claim 8 wherein said buffer layer between said upper and intermediate solar cells comprises a p + type AlGaAs layer and an n + type AlGaAs layer.
References Cited (Backward Citations)
JPS571268A
Cited
JPS58119676A
Cited
JPS58119679A
Cited
JPS58127386A
Cited
US4575577A
Cited
US4681982A
Cited
JPS6214110A
Cited
US4680422A
Cited
US4867801A
Cited
US4631352A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-04-22 | 1994-10-22 | 1995-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-22 | 1998-10-22 | 1999-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-22 | 2002-10-22 | 2003-04-23 | $7700.00 | Window Closed / Lapsed |