Patent US4903089A successfully refreshed from Google Patents.
US4903089A
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Vertical transistor device fabricated with semiconductor regrowth
Assignee: Massachusetts Institute of Technology
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Filing: 1988-02-02
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Granted: 1990-02-20
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Expires: 2008-02-02
Abstract
Abstract A vertical transistor device is characterized by active regions vertically separated by a narrower control region. The control region is defined by conducting layer extensions which extend into a groove within which semiconductor material is regrown during device fabrication. The device is further characterized by regions of isolating material, located horizontally adjacent to the active regions, said isolating material serving to reduce parasitic capacitance and improve thermal distribution within the device, thereby improving frequency and power performance.
Inventors
- 👤 Mark A. Hollis
- 👤 Carl O. Bozler
- 👤 Kirby B. Nichols
- 👤 Normand J. Bergeron, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:46
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/012; H10D30/061; H10D30/202; H10D30/80; H10D30/87; H10D30/871; H10D62/00; H10D62/10; H10D62/113; H10D62/115; H10D62/116; H10D64/00; H10D64/01; H10D64/011; H10W; H10W40/00; H10W40/10; H10D62/80; H10D62/85
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
133 words
A vertical transistor device comprising one or more active cells which comprise: a. first and second semiconductor regions vertically displaced in semiconductor material and separated by a control region; b. isolation regions adjacent to the sides of the first and second semiconductor regions, the isolation regions being formed of a material which is different from the semiconductor material and which has a lower dielectric constant; and c. a conducting layer extending from at least one isolation region, thereby defining the control region, said control region being narrower than at least one of either the first or second semiconductor regions wherein the conducting layer extends beyond the isolation region material to a distance on the order of the zero bias depletion width of the semiconductor due to the isolation region material to semiconductor interface.
Claim 2
Dependent Claim
133 words
A vertical transistor device comprising one or more active cells which comprise: a. first and second semiconductor regions vertically displaced in semiconductor material and separated by a control region; b. isolation regions adjacent to the sides of the first and second semiconductor regions, the isolation regions being formed of a material which is different from the semiconductor material and which has a lower dielectric constant; and c. a conducting layer extending from at least one isolation region, thereby defining the control region, said control region being narrower than at least one of either the first or second semiconductor regions wherein the conducting layer extends beyond the isolation region material to a distance on the order of the zero bias depletion width of the semiconductor due to the isolation region material to semiconductor interface.
Claim 3
Dependent Claim
24 words
A vertical transistor device as in claim 1 wherein the conducting layer vertically separates the isolation layers adjacent the first and second semiconductor regions.
Claim 4
Dependent Claim
15 words
A vertical transistor device as in claim 1 wherein the conducting layer comprises a grating.
Claim 5
Dependent Claim
18 words
A Vertical transistor device as in claim 3 wherein the grating forms depletion regions which form current-limiting channels.
Claim 6
Dependent Claim
15 words
A vertical transistor device as in claim 3 which comprises a vertical field effect transistor.
Claim 7
Dependent Claim
20 words
A vertical transistor device as in claim 3 wherein the space between teeth of the grating defines the control region.
Claim 8
Dependent Claim
27 words
A vertical transistor device as in claim 6 wherein the width of the control region is less than the width of the first and second semiconductor regions.
Claim 9
Dependent Claim
23 words
A vertical transistor device as in claim 3 wherein the conducting layer is selected from the group consisting of tungsten and doped poly-silicon.
Claim 10
Dependent Claim
36 words
A vertical transistor device as in claim 3 wherein the isolation layers contain material selected from the group consisting of diamond, beryllium oxide, aluminum oxide, aluminum nitride, silicon dioxide, silicon nitride, air, and foamed polymeric materials.
Claim 11
Dependent Claim
15 words
A vertical transistor device as in claim 3 wherein the semiconductor material is gallium arsenide.
References Cited (Backward Citations)
US4378629A
Cited
US4530149A
Cited
US4586240A
Cited
US4677451A
Cited
WO1987007432A1
Cited
US4757029A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |