US5205871A
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Monocrystalline germanium film on sapphire
Assignee: UNITED STATES OF AMERIA AS REPRESENTED BY SERETARY OF NAVY
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Filing: 1990-06-01
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Granted: 1993-04-27
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Expires: 2010-06-01
Abstract
Abstract A monocrystalline germanium film is grown on a sapphire substrate with a (1 &upbar& 102) orientation. The substrate is first pretreated to restructure the (1 &upbar& 102) surface plane. Typically, restructuring is accomplished by either an anneal at high temperature or ion bombardment. A monocrystalline germanium layer is grown on the pretreated surface by a vapor deposition process such as molecular beam epitaxy or chemical vapor deposition.
Inventors
- 👤 David J. Godbey
- 👤 Syed B. Qadri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:54
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/80; H10D62/83; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/29; H10P14/2901; H10P14/2921; H10P14/2926; H10P14/32; H10P14/3202; H10P14/3204; H10P14/3211; H10P14/3214; H10P14/3221; H10P14/3242; H10P14/3244; H10P14/3248; H10P14/3258; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/36; Y; Y10; Y10S; Y10S117/00; Y10S117/901; Y10S117/902; Y10S148/00; Y10S148/058; Y10S438/00; Y10S438/967
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
38 words
A germanium on sapphire substrate for a semiconductor device, comprising: a single crystal sapphire substrate which has a surface with an index of plane (1102); and an epitaxial monocrystalline germanium layer on said surface of the sapphire substrate.
Claim 2
Dependent Claim
38 words
A germanium on sapphire substrate for a semiconductor device, comprising: a single crystal sapphire substrate which has a surface with an index of plane (1102); and an epitaxial monocrystalline germanium layer on said surface of the sapphire substrate.
Claim 3
Dependent Claim
23 words
The germanium on sapphire substrate of claim 1, wherein said epitaxial monocrystalline germanium layer has a surface with an index of plane (110).
Claim 4
Dependent Claim
25 words
The germanium on sapphire substrate of claim 1, wherein there is no significant tetragonal distortion in the plane and perpendicular lattices of the germanium layer.
Claim 5
Dependent Claim
17 words
The germanium on sapphire substrate of claim 1, further comprising a silicon layer on the germanium layer.
Claim 6
Dependent Claim
18 words
The germanium on sapphire substrate of claim 1, further comprising a gallium arsenide layer on the germanium layer.
Claim 7
Dependent Claim
22 words
The geranium on saphire substrate of claim 1, further comprising sequentially deposited layers of gallium arsenide and silicon on the germanium layer.
Claim 8
Dependent Claim
60 words
A process for the production of a monocrystalline germanium layer on the r-plane of an α- alumina substrate, comprising the steps of: pretreating said α-alumina substrate to significantly restructure said r-plane surface thus rendering said r-plane surface capable of supporting the epitaxial growth of germanium thereon; vapor depositing a monocrystalline layer of germanium on said r-plane of said pretreated substrate.
Claim 9
Dependent Claim
60 words
A process for the production of a monocrystalline germanium layer on the r-plane of an α- alumina substrate, comprising the steps of: pretreating said α-alumina substrate to significantly restructure said r-plane surface thus rendering said r-plane surface capable of supporting the epitaxial growth of germanium thereon; vapor depositing a monocrystalline layer of germanium on said r-plane of said pretreated substrate.
Claim 10
Dependent Claim
14 words
The process of claim 7, wherein said pretreating step comprises annealing or ion bombardment.
Claim 11
Dependent Claim
22 words
The process of claim 8, wherein said pretreating step comprises annealing the α-alumina substrate at a temperature of from about 1100°-1600° C.
Claim 12
Dependent Claim
20 words
The process of claim 9, wherein said substrate is annealed under vacuum or in the presence of a carrier gas.
Claim 13
Dependent Claim
16 words
The process of claim 9, wherein said substrate is annealed for about 5 to 60 minutes.
Claim 14
Dependent Claim
18 words
The process of claim 9, wherein the substrate is annealed at a temperature of from about 1300°-1500° C.
Claim 15
Dependent Claim
18 words
The process of claim 9, wherein the substrate is annealed at a temperature of from about 1350°-1450° C.
Claim 16
Dependent Claim
14 words
The process of claim 7, wherein said substrate is cleaned prior to said pretreatment.
Claim 17
Dependent Claim
12 words
The process of claim 7, wherein the α-alumina is single crystal sapphire.
Claim 18
Dependent Claim
17 words
The process of 7, wherein said vapor depositing step comprises molecular beam epitaxy or chemical vapor deposition.
Claim 19
Dependent Claim
17 words
The process of 7, wherein said vapor depositing step comprises molecular beam epitaxy or chemical vapor deposition.
Claim 20
Dependent Claim
15 words
The process of claim 16, wherein the germanium layer is grown by molecular beam epitaxy.
Claim 21
Dependent Claim
18 words
The process of claim 17, wherein the germanium layer is grown at a temperature of about 600°-900° C.
Claim 22
Dependent Claim
18 words
The process of claim 18, wherein the germanium layer is grown at a temperature of about 650°-850° C.
Claim 23
Dependent Claim
18 words
The process of claim 9, wherein the germanium layer is grown at a temperature of about 750°-850° C.
Claim 24
Dependent Claim
19 words
The process of claim 7, wherein the α-alumina substrate is subjected to ion bombardment prior to growing germanium thereon.
Claim 25
Dependent Claim
21 words
The process of claim 21, wherein the α-alumina substrate is subjected to ion bombardment with a noble gas during the annealing.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-04-26 | 1996-10-26 | 1997-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-26 | 2000-10-26 | 2001-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-26 | 2004-10-26 | 2005-04-27 | $7700.00 | Window Closed / Lapsed |