US4216490A
Expired / Lapsed
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Static induction transistor
Assignee: Seiko Instruments Inc
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Filing: 1978-03-28
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Granted: 1980-08-05
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Expires: 1998-03-28
Abstract
Abstract A static induction transistor having a channel region between a gate region and a source region of the transistor. Current flowing from the drain region to the source region through the channel region is controlled by a voltage applied to the gate region. An impurity region having a conductivity type opposite that of the channel region is formed in the channel region and is effective to decrease the channel current which will flow when the gate region is biased by a low voltage.
Inventors
- 👤 Toshimi Ohki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:51
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/17; H10D62/213; H10D62/221; H10D62/328; H10D12/00; H10D89/00; H10D89/211; H10D89/213; H10D89/217
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
108 words
In a static induction transistor having a channel region formed between a drain region and a source region, and a gate region formed around said drain region and responsive to a gate voltage applied thereto for controlling current flowing from said drain region through said channel region to said source region, the improvement which comprises: an impurity region formed within said channel region and having a conductivity type opposite that of said channel region, wherein said impurity region has a thickness in the direction of current flow and an impurity concentration effective for decreasing the current when said gate region is biased by a low level gate voltage.
Claim 2
Dependent Claim
108 words
In a static induction transistor having a channel region formed between a drain region and a source region, and a gate region formed around said drain region and responsive to a gate voltage applied thereto for controlling current flowing from said drain region through said channel region to said source region, the improvement which comprises: an impurity region formed within said channel region and having a conductivity type opposite that of said channel region, wherein said impurity region has a thickness in the direction of current flow and an impurity concentration effective for decreasing the current when said gate region is biased by a low level gate voltage.
Claim 3
Dependent Claim
31 words
A static induction transistor according to claim 1, wherein said impurity region is a thin layer within said channel region and remote from both said source region and said drain region.
Claim 4
Dependent Claim
44 words
A static induction transistor according to claim 1, wherein said impurity region is a thin layer within said channel region, remote from both said source region and said drain region, and extending completely across said channel region so as to contact said gate region.
Claim 5
Dependent Claim
38 words
A static induction transistor according to claim 1, further comprising: an injector transistor having a base region and an emitter region, wherein said gate region of the static induction transistor defines a collector region of said injector transistor.
Claim 6
Dependent Claim
24 words
A static induction transistor according to claim 1, wherein said impurity region is formed from the same impurity as that of said gate region.
Claim 7
Dependent Claim
23 words
A static induction transistor according to claims 1 or 5, wherein said gate region is pinched off when said gate region is unbiased.
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) | 1983-08-05 | 1984-02-04 | 1984-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-05 | 1988-02-04 | 1988-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-05 | 1992-02-04 | 1992-08-05 | $7700.00 | Window Closed / Lapsed |