US3982265A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Devices containing aluminum-V semiconductor and method for making
Assignee: AT&T Inc
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Filing: 1975-09-19
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Granted: 1976-09-21
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Expires: 1995-09-19
Abstract
Abstract A high efficiency solar cell having n-type aluminum arsenide grown on a p-type gallium arsenide substrate and protected by a layer of anodic oxide. The aluminum arsenide is deposited by vapor phase epitaxy by reacting high purity arsine, hydrogen chloride and aluminum at approximately 1000°C in an all-alumina reactor tube system. The aluminum arsenide layer is protected from deterioration by first anodizing it in pure water and phosphoric acid at pH 2.0 with a current density of 2-8 milliamperes per square centimeter at room temperature. Second, the anodic oxide so formed is annealed at about 450°C for at least twenty minutes in dry nitrogen. The oxide layer also acts as an antireflective coating. A portion of the oxide layer is etched away to expose a region of the aluminum arsenide to which an electrical contact is applied. The other contact is made to the substrate.
Inventors
- 👤 Wilbur Dexter Johnston, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:59
CPC Classifications
H; H10; H10F; H10F10/00; H10F10/10; H10F10/16; H10F10/163; H04; H04B; H04B10/00; H04B10/40; H04B10/43; H10F55/00; H10F55/18; H10F77/00; H10F77/30; H10F77/306; H10F77/311; H10F77/315; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6324; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69391; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/544; Y10; Y10S; Y10S205/00; Y10S205/923
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
28 words
A p-n junction device comprising: a first layer including III-V semiconductor; a second layer including aluminum-V semiconductor; and a layer of aluminum-V oxide located on said second layer.
Claim 2
Dependent Claim
28 words
A p-n junction device comprising: a first layer including III-V semiconductor; a second layer including aluminum-V semiconductor; and a layer of aluminum-V oxide located on said second layer.
Claim 3
Dependent Claim
28 words
A device as claimed in claim 1 wherein said aluminum-V semiconductor has a Group V constituent comprising arsenic and said first and second layers are substantially lattice matched.
Claim 4
Dependent Claim
15 words
A device as claimed in claim 1 wherein said first layer includes gallium arsenide semiconductor.
Claim 5
Dependent Claim
15 words
A device as claimed in claim 1 wherein said second layer includes aluminum arsenide semiconductor.
Claim 6
Dependent Claim
36 words
A device as claimed in claim 4 wherein said second layer includes aluminum arsenide having an n-type carrier concentration and said first layer has a p-type carrier concentration in a portion adjacent to said second layer.
Claim 7
Dependent Claim
31 words
A device as claimed in claim 5 wherein the carrier concentration in said n-type aluminum arsenide exceeds in magnitude one-half the carrier concentration in the adjacent portion of said first layer.
Claim 8
Dependent Claim
39 words
A photovoltaic device comprising: a first layer including a III-V semiconductor; a second layer of aluminum-V semiconductor of conductivity type opposite to said first layer and disposed adjacent thereto; and a transparent protective coating located on said second layer.
Claim 9
Dependent Claim
39 words
A photovoltaic device comprising: a first layer including a III-V semiconductor; a second layer of aluminum-V semiconductor of conductivity type opposite to said first layer and disposed adjacent thereto; and a transparent protective coating located on said second layer.
Claim 10
Dependent Claim
21 words
A photovoltaic device as claimed in claim 7 wherein said coating is a layer of anodic oxide of said second layer.
Claim 11
Dependent Claim
26 words
A photovoltaic device as claimed in claim 7 wherein said second layer includes aluminum arsenide and said coating is an antireflective layer of anodized aluminum arsenide.
Claim 12
Dependent Claim
59 words
A photovoltaic device as claimed in claim 7 wherein said III-V semiconductor is gallium arsenide having a p-type carrier concentration; said aluminum-V semiconductor is aluminum arsenide having an n-type carrier concentration exceeding 5 × 10 17 and exceeding one half said p-type carrier concentration in magnitude; and said coating is a layer of anodic oxide of said second layer.
Claim 13
Dependent Claim
50 words
In a method of applying a protective coating to a device having an exposed layer of aluminum-V compound the steps of anodically oxidizing said aluminum-V compound in essentially pure water adjusted in pH with phosphoric acid and annealing the anodic oxide so formed at a temperature between 350°C and 520°C.
Claim 14
Dependent Claim
50 words
In a method of applying a protective coating to a device having an exposed layer of aluminum-V compound the steps of anodically oxidizing said aluminum-V compound in essentially pure water adjusted in pH with phosphoric acid and annealing the anodic oxide so formed at a temperature between 350°C and 520°C.
Claim 15
Dependent Claim
39 words
The method of claim 11 wherein said pH is between 1 and 4 and said oxidizing occurs in liquid having a temperature not greater than 70°C and said annealing occurs in an atmosphere inert relative to said anodic oxide.
Claim 16
Dependent Claim
59 words
The method of claim 11 wherein said compound is aluminum arsenide; said pH is between 1.5 and 2.5; said oxidizing occurs at room temperature at a current density between 2 and 8 milliamperes per square centimeter; and said annealing occurs at a temperature between 400° and 450°C for a period between 20 minutes and 2 hours in dry nitrogen.
Claim 17
Dependent Claim
26 words
A device capable of converting radiant energy into electrical energy constructed to include aluminum-V semiconductor having a protective coating produced by the method of claim 11.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-21 | 1980-03-22 | 1980-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-21 | 1984-03-22 | 1984-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-21 | 1988-03-22 | 1988-09-21 | $7700.00 | Window Closed / Lapsed |