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US5945693A
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Field-effect transistor
Assignee: Honda Motor Co Ltd
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Filing: 1995-11-30
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Granted: 1999-08-31
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Expires: 2015-11-30
Abstract
Abstract A field-effect transistor has a channel layer of InGaAs, and a pair of wide bandgap layers disposed one on each side of the channel layer, with respective heterojunctions formed with the channel layer. The channel layer has a thickness ranging from 50 to 150 angstroms, which is substantially the same as two-dimensional electron gas layers that are formed in the channel layer. The wide bandgap layers have the same composition, and the same concentration of an impurity.
Inventors
- 👤 Toshifumi Suzuki
- 👤 Yamato Ishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:36
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/40; H10D30/47; H10D30/471; H10D30/473; H10D30/4732; H10D30/4738; H10D30/4735
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
104 words
A field-effect transistor comprising: a channel layer of InGaAs; and a pair of semiconductor layers having respective wide bandgaps disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layer; said channel layer having such a thickness that two-dimensional electron gas layers produced in the channel layer are regarded as a substantially single two-dimensional electron gas layer; said wide bandgap layers containing respective planar doped layers therein spaced from the respective heterojunctions between said channel layer and said semiconductor layer, and respective undoped spacer layers of the same thickness interposed between said heterojunctions and said planar doped layers.
Claim 2
Dependent Claim
104 words
A field-effect transistor comprising: a channel layer of InGaAs; and a pair of semiconductor layers having respective wide bandgaps disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layer; said channel layer having such a thickness that two-dimensional electron gas layers produced in the channel layer are regarded as a substantially single two-dimensional electron gas layer; said wide bandgap layers containing respective planar doped layers therein spaced from the respective heterojunctions between said channel layer and said semiconductor layer, and respective undoped spacer layers of the same thickness interposed between said heterojunctions and said planar doped layers.
Claim 3
Dependent Claim
19 words
A field-effect transistor according to claim 1, wherein said planar doped layers have the same concentration of a dopant.
Claim 4
Dependent Claim
61 words
A field-effect transistor comprising: a channel layer of InGaAs; and a pair of wide bandgap layers disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layers; said wide bandgap layers containing respective planar doped layers therein spaced substantially the same distance from the respective heterojunctions between said channel layer and said wide bandgap layers.
Claim 5
Dependent Claim
61 words
A field-effect transistor comprising: a channel layer of InGaAs; and a pair of wide bandgap layers disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layers; said wide bandgap layers containing respective planar doped layers therein spaced substantially the same distance from the respective heterojunctions between said channel layer and said wide bandgap layers.
Claim 6
Dependent Claim
92 words
A field-effect transistor comprising: a channel layer of InGaAs; and a pair of wide bandgap layers of Al x Ga 1-x As (0.2<x<0.3) disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layer, each of said wide bandgap layers containing an impurity; said wide bandgap layers having the same composition ratios, the impurities of said wide bandgap layers having the same concentration, and wherein said wide bandgap layers comprise a silicon-doped layer therein having a concentration ranging from 1 to 10×10 12 cm 2 .
Claim 7
Dependent Claim
92 words
A field-effect transistor comprising: a channel layer of InGaAs; and a pair of wide bandgap layers of Al x Ga 1-x As (0.2<x<0.3) disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layer, each of said wide bandgap layers containing an impurity; said wide bandgap layers having the same composition ratios, the impurities of said wide bandgap layers having the same concentration, and wherein said wide bandgap layers comprise a silicon-doped layer therein having a concentration ranging from 1 to 10×10 12 cm 2 .
Claim 8
Dependent Claim
78 words
A field-effect transistor comprising: a channel layer of InGaAs; a pair of undoped wide bandgap layers disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layer; said channel layer having such a thickness that two-dimensional electron gas layers produced in the channel layer are regarded as a substantially single two-dimensional electronic gas layer; and a pair of planar doped layers disposed one on each side of said undoped wide bandgap layer.
Claim 9
Dependent Claim
78 words
A field-effect transistor comprising: a channel layer of InGaAs; a pair of undoped wide bandgap layers disposed one on each side of said channel layer, with respective heterojunctions formed with said channel layer; said channel layer having such a thickness that two-dimensional electron gas layers produced in the channel layer are regarded as a substantially single two-dimensional electronic gas layer; and a pair of planar doped layers disposed one on each side of said undoped wide bandgap layer.
Claim 10
Dependent Claim
16 words
A field-effect transistor according to claim 5 wherein said wide bandgap layer is made of AlGaAs.
Claim 11
Dependent Claim
20 words
A field-effect transistor according to claim 5 wherein a pair of undoped wide bandgap layers have substantially the same thickness.
Claim 12
Dependent Claim
19 words
A field-effect transistor according to claim 5 wherein a pair of undoped wide bandgap layers have the same composition.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2002-08-30 | 2003-03-01 | 2003-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-30 | 2007-03-01 | 2007-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-30 | 2011-03-01 | 2011-08-31 | $7700.00 | Window Closed / Lapsed |