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US4835583A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor device having strained superlattice buffer layers with In-doped GaAs substrate

Assignee: Hitachi Ltd
•
Filing: 1986-08-13
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Granted: 1989-05-30
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Expires: 2006-08-13
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Abstract

Abstract An epitaxial crystal grown layer structure which permits, on an In-doped GaAs substrate, which will be industrially used in large quantities, the growth of an epitaxial layer having the same good quality as the epitaxial layer grown on an undoped GaAs substrate.

Inventors

  • 👤 Makoto Morioka
  • 👤 Tomoyoshi Mishima
  • 👤 Kenji Hiruma
  • 👤 Yoshifumi Katayama
  • 👤 Yasuhiro Shiraki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 23:39
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/29; H10P14/2901; H10P14/2907; H10P14/2911; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3221; H10P14/3242; H10P14/3244; H10P14/3251; H10P14/3252; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3421

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 89 words
A semiconductor device comprising an In-doped GaAs substrate, a buffer layer of a strained superlattice grown on said substrate, and a III-V compound semiconductor layer grown on said buffer layer, said III-V compound semiconductor layer forming an active region of the device and having a lattice constant that is not identical to that of the substrate, said strained superlattice being a laminar structure composed of alternating In-doped GaAs films and III-V compound semiconductor films, wherein the influence of lattice mismatch between said substrate and the active region is reduced.
Claim 2
Dependent Claim 89 words
A semiconductor device comprising an In-doped GaAs substrate, a buffer layer of a strained superlattice grown on said substrate, and a III-V compound semiconductor layer grown on said buffer layer, said III-V compound semiconductor layer forming an active region of the device and having a lattice constant that is not identical to that of the substrate, said strained superlattice being a laminar structure composed of alternating In-doped GaAs films and III-V compound semiconductor films, wherein the influence of lattice mismatch between said substrate and the active region is reduced.
Claim 3
Dependent Claim 114 words
A semiconductor device comprising an In-doped GaAs substrate, a buffer layer of a strained superlattice grown on said substrate, and a III-V compound semiconductor layer grown on said buffer layer, said III-V compound semiconductor layer forming an active region of the device and having a lattice constant that is not identical to that of said substrate, said strained superlattice being a laminar structure composed of alternating (a) III-V compound semiconductor films each having a larger lattice constant than that of said substrate and (b) III-V compound semiconductor films each having a smaller lattice constant than that of the substrate, wherein the influence of lattice mismatch between said substrate and the active region is reduced.
Claim 4
Dependent Claim 114 words
A semiconductor device comprising an In-doped GaAs substrate, a buffer layer of a strained superlattice grown on said substrate, and a III-V compound semiconductor layer grown on said buffer layer, said III-V compound semiconductor layer forming an active region of the device and having a lattice constant that is not identical to that of said substrate, said strained superlattice being a laminar structure composed of alternating (a) III-V compound semiconductor films each having a larger lattice constant than that of said substrate and (b) III-V compound semiconductor films each having a smaller lattice constant than that of the substrate, wherein the influence of lattice mismatch between said substrate and the active region is reduced.
Claim 5
Dependent Claim 20 words
A semiconductor device according to claim 1, further comprising means for allowing a current to flow through said active region.
Claim 6
Dependent Claim 24 words
A semiconductor device according to claim 1, wherein each of the films of the strained superlattice has a thickness in the range of 40Å-170Å.
Claim 7
Dependent Claim 46 words
A semiconductor device according to claim 1, wherein said III-V compound semiconductor layer is a layer selected from the group consisting of a GaAs epitaxially grown layer, an Al x Ga 1-x As epitaxially grown layer, and a GaAs/Al x Ga 1-x As heteroepitaxially grown layer.
Claim 8
Dependent Claim 34 words
A semiconductor device according to claim 1, wherein said active region comprises an n + -type electron supplying layer and a channel layer of electron affinity different than that of said electron supplying layer.
Claim 9
Dependent Claim 30 words
A semiconductor device according to claim 6, wherein said electron supplying layer is formed of n + -Al x Ga 1-x As and said channel layer is formed of GaAs.
Claim 10
Dependent Claim 27 words
A semiconductor device according to claim 7, further comprising an n + -GaAs surface layer on the n + -Al x Ga 1-x As electron supplying layer.
Claim 11
Dependent Claim 20 words
A semiconductor device according to claim 2, further comprising means for allowing a current to flow through said active region.
Claim 12
Dependent Claim 24 words
A semiconductor device according to claim 2, wherein each of the films of the strained superlattice has a thickness in the range of 40Å-170Å.
Claim 13
Dependent Claim 46 words
A semiconductor device according to claim 2, wherein said III-V compound semiconductor layer is a layer selected from the group consisting of a GaAs epitaxially grown layer, an Al x Ga 1-x As epitaxially grown layer, and a GaAs/Al x Ga 1-x As heteroepitaxially grown layer.
Claim 14
Dependent Claim 34 words
A semiconductor device according to claim 2, wherein said active region comprises an n + -type electron supplying layer and a channel layer of electron affinity different than that of said electron supplying layer.
Claim 15
Dependent Claim 30 words
A semiconductor device according to claim 12, wherein said electron supplying layer is formed of n + -Al x Ga 1-x As and said channel layer is formed of GaAs.
Claim 16
Dependent Claim 27 words
A semiconductor device according to claim 13, further comprising an n + -GaAs surface layer on the n + -Al x Ga 1-x As electron supplying layer.

References Cited (Backward Citations)

US4205329A Cited
US4697202A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-05-29 1992-11-28 1993-05-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-05-29 1996-11-28 1997-05-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-05-29 2000-11-28 2001-05-30 $7700.00 Window Closed / Lapsed

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