US3997908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Schottky gate field effect transistor
Assignee: Siemens AG
•
Filing: 1975-03-28
•
Granted: 1976-12-14
•
Expires: 1995-03-28
Abstract
Abstract A Schottky gate field effect transistor of the type comprising a silicon body of one conductivity type on an insulator substrate, and source, drain and gate electrodes is provided with a pn-junction located parallel to the surface of the substrate which produces a space charge zone occupying the zones of the silicon body close to the substrate surface, and a relatively thin active layer is located between the space charge zone and the gate electrode, the active layer having the same type conductivity as the silicon body.
Inventors
- 👤 Heinrich Schloetterer
- 👤 Jenoe Tihanyi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:20
CPC Classifications
H; H10; H10D; H10D86/00; H10D99/00
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
125 words
In a Schottky gate field effect transistor comprising a silicon body of one conductivity type on an insulator substrate, and source, drain and gate electrodes, the improvement which comprises a pn-junction located parallel to the surface of said substrate which produces a space charge zone extending to the surface of said substrate beyond the perimeter of said gate electrode, a relatively thin active layer located between said space charge zone and the gate electrode, said active layer having the same type conductivity as the silicon body and the source and drain areas, and a layer of opposite conductivity type disposed at the interface between said silicon body and said insulator substrate said pn-junction being formed by said layer of opposite conductivity type and said body.
Claim 2
Dependent Claim
125 words
In a Schottky gate field effect transistor comprising a silicon body of one conductivity type on an insulator substrate, and source, drain and gate electrodes, the improvement which comprises a pn-junction located parallel to the surface of said substrate which produces a space charge zone extending to the surface of said substrate beyond the perimeter of said gate electrode, a relatively thin active layer located between said space charge zone and the gate electrode, said active layer having the same type conductivity as the silicon body and the source and drain areas, and a layer of opposite conductivity type disposed at the interface between said silicon body and said insulator substrate said pn-junction being formed by said layer of opposite conductivity type and said body.
Claim 3
Dependent Claim
14 words
A transistor as claimed in claim 1 in which said silicon body is n-conducting.
Claim 4
Dependent Claim
28 words
A transistor as claimed in claim 2 including a layer of p-conducting silicon disposed in close proximity to the interface between said silicon body and said insulator substrate.
Claim 5
Dependent Claim
31 words
A transistor as claimed in claim 3 which includes an area of negative surface charges in the surface of said substrate at said interface which influences said layer of p-conducting silicon.
Claim 6
Dependent Claim
14 words
A transistor as claimed in claim 1 in which said silicon body is p-conducting.
Claim 7
Dependent Claim
28 words
A transistor as claimed in claim 5 including a layer of n-conducting silicon disposed in close proximity to the interface between said silicon body and said insulator substrate.
Claim 8
Dependent Claim
32 words
A transistor as claimed in claim 3 wherein said p-conducting silicon is produced by implantation of boron ions to a charge carrier concentration of 10 14 -10 17 cm - 3 .
Claim 9
Dependent Claim
20 words
A transistor as claimed in claim 3 wherein said p-conducting silicon is produced during epitaxial deposition of said silicon body.
Claim 10
Dependent Claim
17 words
A transistor as claimed in claim 6 wherein said n-conducting silicon is produced by implantation of ions.
Claim 11
Dependent Claim
20 words
A transistor as claimed in claim 6 wherein said n-conducting silicon is produced during epitaxial deposition of said silicon body.
Claim 12
Dependent Claim
31 words
A transistor as claimed in claim 10 which includes an area of positive surface charge in the surface of said substrate at said interface which influences said layer of n-conducting silicon.
Claim 13
Dependent Claim
15 words
A transistor as claimed in claim 1 in which said insulator substrate is a spinel.
Claim 14
Dependent Claim
15 words
A transistor as claimed in claim 12 in which said spinel is a magnesium-aluminum spinel.
Claim 15
Dependent Claim
15 words
A transistor as claimed in claim 1 in which said insulating substrate is a sapphire.
Claim 16
Dependent Claim
33 words
A transistor according to claim 1 which includes highly doped zones of the same conductivity type as the silicon body between the source and gate electrodes and between the gate and drain electrodes.
Claim 17
Dependent Claim
37 words
A transistor according to claim 15 which includes a highly doped active layer in said silicon body of the same conductivity type as the silicon body remote from the interface between said silicon body and said substrate.
Claim 18
Dependent Claim
30 words
A transistor according to claim 15 in which said highly doped zones have charge carrier concentrations of approximately 10 19 cm - 3 to 10 20 cm - 3 .
Claim 19
Dependent Claim
26 words
A transistor according to claim 16 in which the highly doped active layer has a charge carrier concentration of approximately 10 17 cm - 3 .
Claim 20
Dependent Claim
25 words
A transistor according to claim 1 in which the silicon body possesses a charge carrier concentration of less than 10 16 cm - 3 .
Claim 21
Dependent Claim
33 words
A transistor according to claim 4 in which said area of surface charges in the substrate is produced by heat treating the substrate in a hydrogen atmosphere at about 1100° to 1300° C.
References Cited (Backward Citations)
US3783052A
Cited
US3890632A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-12-14 | 1980-06-14 | 1980-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-14 | 1984-06-14 | 1984-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-14 | 1988-06-14 | 1988-12-14 | $7700.00 | Window Closed / Lapsed |