EP0609799A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Improvements in heteroepitaxy by large surface steps
Assignee: Texas Instruments Inc
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Filing: 1994-01-31
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Granted: —
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Expires: 2014-01-31
Abstract
Abstract A method for heteroepitaxial growth and the device wherein a single crystal ceramic substrate 20, preferably Y stabilized zirconia, MgAl 2 O 4 , Al 2 O 3 , 3C-SiC, 6H-SiC or MgO is cut and polished at from about 1.0 to about 10 degrees off axis to produce a substantially flat surface. The atoms on the surface are redistributed on the surface to produce surface steps 22 of at least three lattice spacings. An optional epitaxially grown ceramic buffer layer, preferably AlN or GaN, is then formed on the substrate. Then a layer of semiconductor 24, preferably SiC, AlN when the buffer layer is used and is not AlN or GaN is grown over the substrate and buffer layer, if used.
Inventors
- 👤 Scott R. Summerfelt
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 00:30
CPC Classifications
H; H10; H10D; H10D99/00; H10D62/00; H10D62/80; H10D62/83; H10D62/832; H10D62/8325; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2904; H10P14/2921; H10P14/2924; H10P14/2925; H10P14/2926; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3216; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3408; H10P14/3414; H10P14/3416; H10P14/36; Y; Y10; Y10S; Y10S438/00; Y10S438/931
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
62 words
A method for heteroepitaxial growth, said method comprising the steps of: (a) cutting and polishing a single crystal ceramic substrate at from about 1.0 to about 10 degrees off axis to produce a substantially flat surface; (b) redistributing atoms on said surface to produce surface steps of at least three lattice spacings; and (c) growing a layer of semiconductor over said substrate.
Claim 2
Dependent Claim
23 words
The method of claim 1 further including the step of epitaxially growing a ceramic buffer layer on said substrate prior to step (c).
Claim 3
Dependent Claim
24 words
The method of claim 1, wherein said substrate is selected from the group consisting of y stabilized zirconia, MgAl₂O₄, Al₂O₃, 3C-SiC, 6H-SiC and MgO.
Claim 4
Dependent Claim
24 words
The method of claim 2, wherein said substrate is selected from the group consisting of Y stabilized zirconia, MgAl₂O₄, Al₂O₃, 3C-SiC, 6H-Sic and MgO.
Claim 5
Dependent Claim
16 words
The method of claim 2, wherein said ceramic buffer layer is one of AlN or GaN.
Claim 6
Dependent Claim
16 words
The method of claim 4, wherein said ceramic buffer layer is one of AlN or GaN.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 8
Dependent Claim
15 words
The method of claim 2 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 9
Dependent Claim
15 words
The method of claim 3 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 10
Dependent Claim
15 words
The method of claim 4 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 11
Dependent Claim
14 words
The method of claim 5 wherein said semiconductor is one of SiC or GaN.
Claim 12
Dependent Claim
14 words
The method of claim 6 wherein said semiconductor is one of SiC or GaN.
Claim 13
Dependent Claim
28 words
The method of claim 10, wherein said step of redistributing atoms on said surface is by heating said substrate to at least 1200°C for at least 1 hour.
Claim 14
Dependent Claim
52 words
The method of claim 1, wherein said step of epitaxially growing a semiconductor on said substrate utilizes an initial epitaxy at a first temperature, then a second epitaxial growth an additional thickness of said semiconductor at a second temperature, where said second temperature is at least 100°C higher than said first temperature.
Claim 15
Dependent Claim
52 words
The method of claim 14 wherein said step of epitaxially growing a semiconductor on said substrate utilizes an initial epitaxy at a first temperature, then a second epitaxial growth an additional thickness of said semiconductor at a second temperature, where said second temperature is at least 100°C higher than said first temperature.
Claim 16
Dependent Claim
56 words
A heteroepitaxial device comprising: (a) a polished single crystal ceramic substrate cut at from about 1.0 to about 10 degrees off axis to produce a substantially flat surface; (b) the atoms on said surface having been redistributed to produce surface steps of at least three lattice spacings; and (c) a layer of semiconductor over said substrate.
Claim 17
Dependent Claim
24 words
The device of claim 16 further including an epitaxially grown ceramic buffer layer between said surface of said substrate and said layer of semiconductor.
Claim 18
Dependent Claim
24 words
The device of claim 16, wherein said substrate is selected from the group consisting of Y stabilized zirconia, MgAl₂O₄, Al₂O₃, 3C-SiC, 6H-Sic and MgO.
Claim 19
Dependent Claim
24 words
The device of claim 17, wherein said substrate is selected from the group consisting of Y stabilized zirconia, MgAl₂O₄, Al₂O₃, 3C-SiC, 6H-SiC and MgO.
Claim 20
Dependent Claim
16 words
The device of claim 17, wherein said ceramic buffer layer is one of AlN or GaN.
Claim 21
Dependent Claim
16 words
The device of claim 19, wherein said ceramic buffer layer is one of AlN or GaN.
Claim 22
Dependent Claim
15 words
The device of claim 16 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 23
Dependent Claim
15 words
The device of claim 17 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 24
Dependent Claim
15 words
The device of claim 18 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 25
Dependent Claim
15 words
The device of claim 19 wherein said semiconductor is one of SiC, AlN or GaN.
Claim 26
Dependent Claim
14 words
The device of claim 20 wherein said semiconductor is one of SiC or GaN.
Claim 27
Dependent Claim
12 words
The device of claim 21 semiconductor is one of SiC or GaN.
Claim 28
Independent Claim
83 words
A method of heteroepitaxial growth comprising the steps of: (a) providing a single crystal ceramic substrate; (b) producing a substantially flat surface on said substrate by cutting and polishing said substrate at from about 1 to about 10 degrees off axis in a particle crystallographic direction; (c) producing suface steps of at least three lattice spacings which are parallel to at least two crystallographic directions by redistributing atoms on said substantially flat surface; and (d) growing a layer of semiconductor over said surface.
Claim 29
Dependent Claim
14 words
The method of claim 28 wherein said semiconductor is one of SiC. and GaN.
Claim 30
Dependent Claim
24 words
The method of claim 28, wherein said substrate is selected from the group consisting of Y stabilized zirconia, MgAl₂O₄, A1₂O₃, 3C-SiC, 6H-SiC and MgO.
Claim 31
Dependent Claim
24 words
The method of claim 29, wherein said substrate is selected from the group consisting of Y stabilized zirconia, MgAl₂O₄, Al₂O₃, 3C-SiC, 6H-Sic and MgO.
References Cited (Backward Citations)
No citation records indexed.
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