Patent US3990902A successfully refreshed from Google Patents.
US3990902A
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Magnesium-titanate-comprising spinel single crystal substrate for semiconductor devices
Assignee: Tokin Corp
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Filing: 1975-07-29
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Granted: 1976-11-09
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Expires: 1995-07-29
Abstract
Abstract A spinel single crystal substrate for epitaxial growth thereon of a semiconductor layer to manufacture semiconductor devices. Magnesium titanate is substituted for at least a portion of magnesium aluminate of which the spinel essentially consist in general. A preferred mol ratio of the magnesium titanate to the magnesium aluminate is between 5:95 and 40:60 when a silicon layer is to be epitaxially grown on the substrate as the semiconductor layer.
Inventors
- 👤 Jun-ichi Nishizawa
- 👤 Mitsuhiro Kimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:54
CPC Classifications
C; C30; C30B; C30B19/00; C30B19/12; H; H10; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2921; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
38 words
In a substrate consisting of a magnesium aluminate class spinel single crystal for epitaxial growth thereon of a semiconductor layer, the improvement wherein magnesium titanate is substituted for at least a portion of magnesium aluminate of the spinel.
Claim 2
Dependent Claim
38 words
In a substrate consisting of a magnesium aluminate class spinel single crystal for epitaxial growth thereon of a semiconductor layer, the improvement wherein magnesium titanate is substituted for at least a portion of magnesium aluminate of the spinel.
Claim 3
Dependent Claim
41 words
A substrate as claimed in claim 1, wherein a mol ratio of the magnesium titanate to the magnesium aluminate is between 5:95 and 40:60, whereby said substrate is adapted to epitaxial growth thereon of a silicon layer as said semiconductor layer.
Claim 4
Dependent Claim
16 words
A substrate as claimed in claim 2, wherein said mol ratio is between 12:88 and 30:70.
Claim 5
Dependent Claim
46 words
A substrate as claimed in claim 1, wherein a mol ratio of the magnesium titanate to the magnesium aluminate is approximately 5:5, whereby said substrate is adapted to epitaxial growth thereon of one of a germanium layer and a gallium arsenide layer as said semiconductor layer.
Claim 6
Dependent Claim
42 words
A substrate as claimed in claim 1, wherein a mol ratio of the magnesium titanate to the magnesium aluminate is between 1:99 and 46:54, whereby said substrate is adapted to epitaxial growth thereon of a gallium phosphide layer as said semiconductor layer.
Claim 7
Dependent Claim
16 words
A substrate as claimed in claim 5, wherein said mol ratio is between 17:83 and 36:64.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-11-09 | 1980-05-10 | 1980-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-09 | 1984-05-10 | 1984-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-09 | 1988-05-10 | 1988-11-09 | $7700.00 | Window Closed / Lapsed |