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US5049954A
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GaAs field effect semiconductor device having Schottky gate structure
Assignee: Toshiba Corp
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Filing: 1989-12-05
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Granted: 1991-09-17
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Expires: 2009-12-05
Abstract
Abstract A Schottky gate electrode structure of a GaAs field effect semiconductor device comprises a Ti film having a thickness of 2 nm to 25 nm and provided adherently on a GaAs substrate including source and drain regions, and a refractory electrode film provided on the Ti film and formed of a material selected from W, Mo, Cr, Ta, Nb, V, Hf, Zr, nitrides of these metals, silicides of these metals, carbides of these metals, Ti-W alloys, WSixNy, TiNx, and TiSix. Adhesion of the refractory electrode film to the GaAs substrate is increased, and heat resisting properties of Schottky characteristics are improved according to the thin Ti film.
Inventors
- 👤 Kizashi Shimada
- 👤 Tatsuo Akiyama
- 👤 Yutaka Koshino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:55
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/6729; H10D30/6737; H10D30/6738; H10D30/674; H10D30/675; H10D64/00; H10D64/60; H10D64/64; H10D62/00; H10D62/80; H10D62/85
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
68 words
A GaAs field effect semiconductor device, comprising: a GaAs semiconductor substrate including source and drain regions; and a Schottky gate electrode between the source and drain regions of said GaAs semiconductor substrate, said Schottky gate electrode including: a Ti film having a thickness of greater than or equal to 2 nm and less than or equal to 25 nm, and a refractory electrode film on said Ti film.
Claim 2
Dependent Claim
68 words
A GaAs field effect semiconductor device, comprising: a GaAs semiconductor substrate including source and drain regions; and a Schottky gate electrode between the source and drain regions of said GaAs semiconductor substrate, said Schottky gate electrode including: a Ti film having a thickness of greater than or equal to 2 nm and less than or equal to 25 nm, and a refractory electrode film on said Ti film.
Claim 3
Dependent Claim
54 words
The GaAs field effect semiconductor device of claim 1, in which said refractory electrode film includes a material selected from W, Mo, Cr, Ta, Nb, V, Hf, Zr, nitrides of these materials, silicides of these materials, carbides of these materials, Ti-W alloys, Wsi x N y , TiN x , and TiSi x .
Claim 4
Dependent Claim
20 words
The GaAs field effect semiconductor device of claim 1, further comprising a silicon nitride film on said Schottky gate electrode.
References Cited (Backward Citations)
JPS5998553A
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JPS59119867A
Cited
US4574298A
Cited
FR2550889A1
Cited
JPS6116577A
Cited
JPS62259474A
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EP0275905A2
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JPS63258066A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-16 | 1995-03-18 | 1995-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-16 | 1999-03-18 | 1999-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-16 | 2003-03-18 | 2003-09-17 | $7700.00 | Window Closed / Lapsed |