Patent US4398056A successfully refreshed from Google Patents.
US4398056A
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Solar cell with reflecting grating substrate
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1981-07-23
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Granted: 1983-08-09
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Expires: 2001-07-23
Abstract
Abstract A solar cell which includes a thin layer of active material bounded on the side toward the incident light with an antireflection coating and bounded on the other side by a reflecting diffraction grating to internally reflect the incident light back into the active material.
Inventors
- 👤 Ping Sheng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:58
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/30; H10F77/306; H10F77/311; H10F77/315; H10F77/40; H10F77/42; H10F77/48; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/52
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
81 words
A solar cell comprising: (a) a rectangular diffraction grating coated with a layer of reflecting material on its grating surface; and (b) an active layer of semiconductor material formed on said layer of reflecting material; wherein said diffraction grating has a groove periodicity and depth such that enhancement of absorption of incident light within a desired wavelength range is optimized with respect to the index of refraction and the thickness of the active material and dielectric constant of said reflecting material.
Claim 2
Dependent Claim
81 words
A solar cell comprising: (a) a rectangular diffraction grating coated with a layer of reflecting material on its grating surface; and (b) an active layer of semiconductor material formed on said layer of reflecting material; wherein said diffraction grating has a groove periodicity and depth such that enhancement of absorption of incident light within a desired wavelength range is optimized with respect to the index of refraction and the thickness of the active material and dielectric constant of said reflecting material.
Claim 3
Dependent Claim
14 words
The solar cell of claim 1, wherein said layer of active material is silicon.
Claim 4
Dependent Claim
12 words
The solar cell of claim 2 wherein said reflecting material is silver.
Claim 5
Dependent Claim
17 words
The solar cell of claim 2 wherein said desired wavelength range is 0.55 μm and 1.1 μm.
Claim 6
Dependent Claim
14 words
The solar cell of claim 1 wherein said reflecting material is silver or aluminum.
Claim 7
Dependent Claim
54 words
The solar cell of claim 1 wherein said active layer is polycrystalline silicon, said reflecting material is silver, the thickness of said active layer is about 1 μm, said period of said grating has a value between 0.35 μm and 0.45 μm, and said depth has a value between 0.065 μm and 0.085 μm.
Claim 8
Dependent Claim
15 words
The solar cell of claim 1 wherein said diffraction grating is a two-dimensional rectangular array.
Claim 9
Dependent Claim
52 words
The solar cell of claim 7 wherein said active layer is amorphous silicon of thickness about 0.5 μm, said reflecting layer is silver, said period of said grating has a value between 0.25 μm and 0.35 μm and said depth of said grating has a value between 0.07 μm and 0.09 μm.
Claim 10
Dependent Claim
15 words
The solar cell of claim 1 wherein said diffraction grating is a square-wave diffraction grating.
References Cited (Backward Citations)
US3973994A
Cited
US4328390A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-08 | 1987-02-07 | 1987-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-08 | 1991-02-07 | 1991-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-08 | 1995-02-07 | 1995-08-09 | $7700.00 | Window Closed / Lapsed |