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US5846844A
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Method for producing group III nitride compound semiconductor substrates using ZnO release layers
Assignee: Toyoda Gosei Co Ltd
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Filing: 1996-02-07
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Granted: 1998-12-08
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Expires: 2016-02-07
Abstract
Abstract A nitrogen-group III compound semiconductor satisfying the formula Al x Ga y In 1-x-y N, inclusive of x=0, y=0 and x=y=0, and a method for producing the same comprising the steps of forming a zinc oxide (ZnO) intermediate layer on a sapphire substrate, forming a nitrogen-group III semiconductor layer satisfying the formula Al x Ga y In 1-x-y N, inclusive of x=0, y=0 and x=y=0 on the intermediate ZnO layer, and separating the intermediate ZnO layer by wet etching with an etching liquid only for the ZnO layer.
Inventors
- 👤 Isamu Akasaki
- 👤 Hiroshi Amano
- 👤 Kazumasa Hiramatsu
- 👤 Theeradetch Detchprohm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:10
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H10H20/0137; H10D; H10D86/00; H10D86/01; H10H20/0133; H10H20/01335; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/24; H10P14/29; H10P14/2901; H10P14/2907; H10P14/2908; H10P14/2921; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3216; H10P14/3224; H10P14/3226; H10P14/3242; H10P14/3244; H10P14/3248; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3416; H10P14/3438; H10P14/3441; H10P14/3442; H10P14/3444; H10P14/38; Y; Y10; Y10S; Y10S117/00; Y10S117/915; Y10S148/00; Y10S148/065; Y10S148/113; Y10S148/135
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
142 words
A method for producing a semiconductor comprising the steps of: forming an intermediate zinc oxide (ZnO) layer on a sapphire substrate, said immediate ZnO layer having a thickness of about 10 nm to 1 μm; forming a semiconductor substrate on said intermediate ZnO layer, said semiconductor substrate being made of a nitrogen-group III compound satisfying the formula Al x Ga y In l-x-y N, inclusive of x=0, y=0 and x=y=0; etching said intermediate ZnO layer with etching liquid capable of selectively etching ZnO so that the ZnO layer is substantially removed from between the semiconductor substrate and the sapphire substrate; separating said semiconductor substrate from said sapphire substrate by said etching; and epitaxially growing a semiconductor layer made of nitrogen-group III compound satisfying the formula Al x Ga y In 1-x-y N, inclusive of x=0, y=0 and x=y=0 on said semiconductor substrate.
Claim 2
Independent Claim
142 words
A method for producing a semiconductor comprising the steps of: forming an intermediate zinc oxide (ZnO) layer on a sapphire substrate, said immediate ZnO layer having a thickness of about 10 nm to 1 μm; forming a semiconductor substrate on said intermediate ZnO layer, said semiconductor substrate being made of a nitrogen-group III compound satisfying the formula Al x Ga y In l-x-y N, inclusive of x=0, y=0 and x=y=0; etching said intermediate ZnO layer with etching liquid capable of selectively etching ZnO so that the ZnO layer is substantially removed from between the semiconductor substrate and the sapphire substrate; separating said semiconductor substrate from said sapphire substrate by said etching; and epitaxially growing a semiconductor layer made of nitrogen-group III compound satisfying the formula Al x Ga y In 1-x-y N, inclusive of x=0, y=0 and x=y=0 on said semiconductor substrate.
Claim 3
Dependent Claim
57 words
The method of claim 1, wherein said semiconductor layer comprises at least an n-type nitrogen-group III compound semiconductor satisfying the formula Al x Ga y In 1-x-y N, inclusive of x=0, y=0 and x=y=0, and a p-type nitrogen-group III compound semiconductor satisfying the formula Al x Ga y In 1-x-y N, inclusive of x=0, y=0 and x=y=0.
Claim 4
Dependent Claim
12 words
The method of claim 1, wherein said semiconductor substrate includes gallium nitride.
Claim 5
Dependent Claim
19 words
The method of claim 1, wherein said ZnO layer is formed on said sapphire substrate by RF sputtering ZnO.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2001-12-07 | 2002-06-08 | 2002-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-12-07 | 2006-06-08 | 2006-12-08 | $3760.00 | Window Closed / Lapsed |
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