Patent EP0865088A2 successfully refreshed from Google Patents.
EP0865088A2
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EP
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Epitaxial wafer having a gallium nitride epitaxial layer deposited on semiconductor substrate and method for preparing the same
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1998-03-16
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Granted: —
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Expires: 2018-03-16
Abstract
Abstract The present invention provides an epitaxial wafer comprising a (111) substrate of a semiconductor having cubic crystal structure, a first GaN layer having a thickness of 60 nanometers or more, a second GaN layer having a thickness of 0.1µm or more and a method for preparing it.
Inventors
- 👤 Kensaku Motoki
- 👤 Masato Matsushima
- 👤 Katsushi Akita
- 👤 Mitsuru Shimazu
- 👤 Kikurou Takemoto
- 👤 Hisashi Seki
- 👤 Akinori Koukitu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 21:23
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3416; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H10H20/0137; H10P14/24; H10P14/29; H10P14/2901; H10P14/2907; H10P14/2911; H10P14/2926; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3216
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
40 words
An epitaxial wafer comprising a (111) substrate
of a semiconductor having a cubic crystal structure, a
first GaN layer having a thickness of 60 nm or more,
and a second GaN layer having a thickness of 0.1 µm or
more.
Claim 2
Dependent Claim
21 words
An epitaxial wafer as claimed in Claim 1, wherein
the first GaN layer has a thickness of 200 nm or less.
Claim 3
Dependent Claim
24 words
An epitaxial wafer as claimed in Claim 1 or Claim
2, wherein the second GaN layer has a thickness of
5 µm or less.
Claim 4
Dependent Claim
30 words
An epitaxial wafer as claimed in any one of
Claims 1 to 3, wherein the (111) substrate of a
semiconductor having a cubic crystal structure is a
GaAs (111) substrate.
Claim 5
Dependent Claim
25 words
An epitaxial wafer as claimed in Claim 4, wherein
the GaAs (111) substrate is a GaAs (111) A-plane
substrate or a GaAs (111) B-plane substrate.
Claim 6
Independent Claim
119 words
A method for preparing an epitaxial wafer
comprising the steps of: supplying a first mixture of material gases
comprising a metalorganic including Ga and HCl and a
second mixture of material gases comprising NH 3 into a
chamber heated by a heat source disposed outside of
said chamber; growing a buffer layer by vapour deposition on a
substrate at a first temperature disposed in the
chamber; improving the crystallinity of the buffer layer
by increasing the substrate temperature from the first
temperature; and supplying said first and second mixtures of
material gases into said chamber in which the
substrate is heated at a second temperature higher
than said first temperature to grow a GaN layer on
said buffer layer.
Claim 7
Independent Claim
137 words
A method for preparing an epitaxial wafer
comprising the steps of: supplying a first mixture of material gases
comprising HCl and a second mixture of material gases
comprising NH 3 into a chamber heated by a heat source
disposed outside of said chamber; forming GaCl by reacting metal Ga contained in a
vessel in said chamber with HCl included in said first
mixture of material gases; growing a buffer layer by vapour deposition on a
substrate at a first temperature disposed in the
chamber; improving the crystallinity of the buffer layer
by increasing the substrate temperature from the first
temperature; and supplying said first and second mixtures of
material gases into said chamber in which the
substrate is heated at a second temperature higher
than said first temperature to grow a GaN layer on
said buffer layer.
Claim 8
Dependent Claim
22 words
A method as claimed in Claim 6 or 7, wherein said
first temperature is in the range of from 400 to
600°C.
Claim 9
Independent Claim
25 words
A method as claimed in any one of Claims 6 to 8,
wherein said second temperature is in the range of
from 850 to 1000°C.
Claim 10
Independent Claim
41 words
A method as claimed in any one of Claims 6 to 9,
wherein said step of improving the crystallinity of
the buffer layer by increasing the substrate
temperature from the first temperature is conducted
with supplying NH 3 onto the substrate.
Claim 11
Independent Claim
30 words
A method as claimed in any one of Claims 6 to 10,
wherein said GaN layer is grown at a growth rate in
the range of from 4 to 10µm/hour
References Cited (Backward Citations)
No citation records indexed.
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