US4201798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of applying an antireflective coating to a solar cell
Assignee: BP Solar International LLC
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Filing: 1977-09-30
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Granted: 1980-05-06
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Expires: 1997-09-30
Abstract
Abstract A tantalum oxide antireflective coating is applied to a surface of a solar energy cell by depositing a layer of a suboxide of tantalum on the surface and then oxidizing the layer to an oxide approaching Ta 2 O 5 .
Inventors
- 👤 Joseph Lindmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:03
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/30; H10F77/306; H10F77/311; H10F77/315; Y; Y02; Y02E; Y02E10/00; Y02E10/50
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
85 words
A method of applying an antireflective coating to a surface of a solar energy cell, said surface being adapted to absorb light impinging thereon, comprising forming a nonstoichiometric mix of tantalum and oxygen in solid form in such proportion that, on subsequent deposition the increasing thickness of the layer of suboxide deposited will be visually apparent by changes in color from gold to purple or blue, and depositing a layer of a suboxide of tantalum of desired thickness on the light-absorbing surface of the cell.
Claim 2
Independent Claim
85 words
A method of applying an antireflective coating to a surface of a solar energy cell, said surface being adapted to absorb light impinging thereon, comprising forming a nonstoichiometric mix of tantalum and oxygen in solid form in such proportion that, on subsequent deposition the increasing thickness of the layer of suboxide deposited will be visually apparent by changes in color from gold to purple or blue, and depositing a layer of a suboxide of tantalum of desired thickness on the light-absorbing surface of the cell.
Claim 3
Dependent Claim
19 words
A method as claimed in claim 1, in which the mix is formed from tantalum pentoxide and elemental tantalum.
Claim 4
Dependent Claim
26 words
A method as claimed in claim 2, in which the ratio of tantalum pentoxide to elemental tantalum in the mix is from about 1:2 to 5:1.
Claim 5
Dependent Claim
23 words
A method as claimed in claim 3, in which the ratio of tantalum pentoxide to elemental tantalum in the mix is about 3:1.
Claim 6
Dependent Claim
16 words
A method as claimed in claim 1, in which said mix comprises reduced oxides of tantalum.
Claim 7
Dependent Claim
58 words
A method as claimed in claim 1, in which the coated cell is thereafter heated in an oxidizing atmosphere at a temperature above about 400° C. for a period of time sufficient to oxidize the layer of tantalum suboxide to an oxide approaching Ta 2 O 5 and having an index of refraction of about 2.1 to 2.3.
Claim 8
Dependent Claim
22 words
a method as claimed in claim 6, in which the coated cell is heated at about 450° C. for about 30 seconds.
Claim 9
Dependent Claim
36 words
A method as claimed in claim 1, in which the deposition of said layer of a suboxide of tantalum on the light-absorbing surface of the cell is accomplished by electron beam evaporation of said non-stoichiometric mix.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-05-06 | 1983-11-05 | 1984-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-06 | 1987-11-05 | 1988-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-06 | 1991-11-05 | 1992-05-06 | $7700.00 | Window Closed / Lapsed |