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US5332451A
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Epitaxially grown compound-semiconductor crystal
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1992-04-29
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Granted: 1994-07-26
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Expires: 2012-04-29
Abstract
Abstract An epitaxially grown compound-semiconductor crystal comprising a substrate, a buffer layer formed directly or indirectly on the substrate, and an active layer formed on the buffer layer. The buffer layer comprises (A) a high-resistivity AlGaAs or AlGaInP layer doped with oxygen or/and a transition metal and, formed thereon, (B) a layer consisting of high-purity GaAs, InGaP, or AlGaAs.
Inventors
- 👤 Masahiko Hata
- 👤 Noboru Fukuhara
- 👤 Takayoshi Maeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:30
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/80; H10D30/87; H10D30/877; H10D62/00; H10D62/80; H10D62/82; H10D62/824; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2907; H10P14/2911; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3218; H10P14/3221; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3418; H10P14/3421; H10P14/3438; H10P14/3441; H10P14/3446
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
58 words
An epitaxially grown compound-semiconductor crystal comprising a substrate, a buffer layer formed directly or indirectly on said substrate, and an active layer formed on said buffer layer, said buffer layer comprising (A) a high-resistivity AlGaAs or AlGaInP layer doped with oxygen or/and a transition metal and, formed thereon, (B) a layer consisting of high-purity GaAs, InGaP, or AlGaAs.
Claim 2
Dependent Claim
58 words
An epitaxially grown compound-semiconductor crystal comprising a substrate, a buffer layer formed directly or indirectly on said substrate, and an active layer formed on said buffer layer, said buffer layer comprising (A) a high-resistivity AlGaAs or AlGaInP layer doped with oxygen or/and a transition metal and, formed thereon, (B) a layer consisting of high-purity GaAs, InGaP, or AlGaAs.
Claim 3
Dependent Claim
38 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 1, which further comprises an undoped GaAs or InP layer formed between said substrate and said high-resistivity AlGaAs or AlGaInP layer (A) doped with oxygen or/and a transition metal.
Claim 4
Dependent Claim
24 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 1, wherein said layer (A) is a high-resistivity AlGaAs or AlGaInP layer doped with oxygen.
Claim 5
Dependent Claim
35 words
An epitaxially grown compound-semiconductor crystal as claimed in any one of claims 1 to 3, wherein said layer (A) is a high-resistivity AlGaAs layer having a composition of formula Al x Ga.sub.(1-x) As, where 0.1<x<0.8.
Claim 6
Dependent Claim
27 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 4, wherein said high-resistivity AlGaAs layer (A) has a composition of formula Al x Ga.sub.(1-x) As, where 0.2≦×≦0.7.
Claim 7
Dependent Claim
44 words
An epitaxially grown compound-semiconductor crystal as claimed in any one of claims 1 to 3, wherein said layer (A) is a high-resistivity AlGaInP layer having a composition of the formula Al x In y Ga.sub.(1-x-y) P, where 0<x≦(about 0.51) and y is about 0.49.
Claim 8
Dependent Claim
47 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 1, wherein said high-resistivity AlGaAs or AlGaInP layer (A) doped with oxygen or/and a transition metal has a total concentration of oxygen and transition metal of from 1×10 16 atoms/cm 3 to about 1×10 21 atoms/cm 3 .
Claim 9
Dependent Claim
36 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 7, wherein said layer (A) has a total concentration of oxygen and transition metal of from 1×10 17 atoms/cm 3 to about 1×10 20 atoms/cm 3 .
Claim 10
Dependent Claim
40 words
An epitaxially grown compound-semiconductor crystal as claimed in any one of claims 1 to 3, wherein said high-resistivity AlGaAs or AlGaInP layer (A) doped with oxygen or/and a transition metal has a thickness of from 2,000 Å to 5 μm.
Claim 11
Dependent Claim
24 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 9, wherein said layer (A) has a thickness of from 5,000 Å to 5 μm.
Claim 12
Dependent Claim
40 words
An epitaxially grown compound-semiconductor crystal as claimed in any one of claims 1 to 3, wherein said layer (B) consisting of high-purity GaAs, InGaP, or AlGaAs has an active defect concentration of less than 1×10 16 per cm 3 .
Claim 13
Dependent Claim
27 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 11, wherein said layer (B) has an active defect concentration of 1×10 15 per cm 3 or less.
Claim 14
Dependent Claim
36 words
An epitaxially grown compound-semiconductor crystal as claimed in any one of claims 1 to 3, wherein said layer (B) consisting of high-purity GaAs, InGaP, or AlGaAs has a thickness of from 1,000 Å to 20,000 Å.
Claim 15
Dependent Claim
24 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 13, wherein said layer (B) has a thickness of from 3,000 Å to 20,000 Å.
Claim 16
Dependent Claim
24 words
An epitaxially grown compound-semiconductor crystal as claimed in claim 14, wherein said layer (B) has a thickness of from 5,000 Å to 10,000 Å.
Claim 17
Dependent Claim
42 words
An epitaxially grown compound-semiconductor crystal as claimed in any one of claims 1 to 3, wherein said active layer is an n-type GaAs or n-type InGaP layer, said epitaxially grown compound-semiconductor crystal being for use in the fabrication of a field-effect transistor.
Claim 18
Dependent Claim
52 words
An epitaxially grown compound-semiconductor crystal for a field-effect transistor, which comprises a GaAs substrate having consecutively thereon an undoped GaAs layer; a high-resistivity AlGaAs or AlGaInP layer (A) doped with oxygen or/and a transition metal; a high-purity GaAs, InGaP, or AlGaAs layer (B); and an n-type GaAs or n-type InGaP active layer.
Claim 19
Dependent Claim
52 words
An epitaxially grown compound-semiconductor crystal for a field-effect transistor, which comprises a GaAs substrate having consecutively thereon an undoped GaAs layer; a high-resistivity AlGaAs or AlGaInP layer (A) doped with oxygen or/and a transition metal; a high-purity GaAs, InGaP, or AlGaAs layer (B); and an n-type GaAs or n-type InGaP active layer.
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| 3.5 Years (Year 4) | 1997-07-25 | 1998-01-24 | 1998-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-25 | 2002-01-24 | 2002-07-26 | $3760.00 | Window Closed / Lapsed |
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