Patent US4801995A successfully refreshed from Google Patents.
US4801995A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device
Assignee: Toshiba Corp
•
Filing: 1985-12-20
•
Granted: 1989-01-31
•
Expires: 2005-12-20
Abstract
Abstract A semiconductor device includes a metal film, not in ohmic contact with a guard ring region (a second region). The metal film is formed on that surface portion of an insulating film under which the guard ring region is formed to surround a base region (a first region) of a planar transistor. In this arrangement, a planar semiconductor device with a high withstand voltage, which is free of short-circuiting between electrodes upon the measurement of the withstand voltage and involves no degeneration of the withstand voltage resulting from an atmospheric humidity, can be obtained. The metal film, which is not in contact with the guard ring region, is "electrically floated", i.e., is not in contact with any area inclusive of the guard ring region.
Inventors
- 👤 Masaaki Iwanishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:25
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/40; H10D10/421; H10D30/00; H10D30/60; H10D30/64; H10D30/66; H10D30/668; H10D62/00; H10D62/10; H10D62/102; H10D62/103; H10D62/105; H10D62/106; H10D62/113; H10D64/00; H10D64/111; H10D64/118
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
124 words
A semiconductor device comprising: a first region formed in a semiconductor substrate, said semiconductor substrate being of a first conductivity type and said first region being of a second conductivity type; a second region of the second conductivity type formed to surround the outer side of said first region, said second region being a guard ring for said first region; an insulating film formed on the surface of the semiconductor substrate; a first electrode formed on said insulating film, said first electrode being in ohmic contact with said first region; and a metal film formed on said surface portion of said insulating film situated above said second region, said metal film being electrically isolated from elements of said semiconductor device including said second region.
Claim 2
Dependent Claim
124 words
A semiconductor device comprising: a first region formed in a semiconductor substrate, said semiconductor substrate being of a first conductivity type and said first region being of a second conductivity type; a second region of the second conductivity type formed to surround the outer side of said first region, said second region being a guard ring for said first region; an insulating film formed on the surface of the semiconductor substrate; a first electrode formed on said insulating film, said first electrode being in ohmic contact with said first region; and a metal film formed on said surface portion of said insulating film situated above said second region, said metal film being electrically isolated from elements of said semiconductor device including said second region.
Claim 3
Dependent Claim
21 words
A semiconductor device according to claim 1, in which said second region has a ring-like shape which surrounds said first region.
Claim 4
Dependent Claim
21 words
A semiconductor device according to claim 1, in which said second region is exposed on the surface of said semiconductor substrate.
Claim 5
Dependent Claim
21 words
A semiconductor device according to claim 2, in which said second region is exposed on the surface of said semiconductor substrate.
Claim 6
Dependent Claim
17 words
A semiconductor device according to claim 1, in which plural regions are provided for said second region.
Claim 7
Dependent Claim
26 words
A semiconductor device according to claim 1, in which said second region comprises a plurality of coaxial ring-shaped regions each of which surrounds said first region.
Claim 8
Dependent Claim
17 words
A semiconductor device according to claim 3, in which plural regions are provided for said second region.
Claim 9
Dependent Claim
26 words
A semiconductor device according to claim 3, in which said second region comprises a plurality of coaxial ring-shaped regions each of which surrounds said first region.
Claim 10
Dependent Claim
34 words
A semiconductor device according to claim 5, in which said metal film is formed on that surface portion of said insulating film which is situated above said second region nearest to said first region.
Claim 11
Dependent Claim
34 words
A semiconductor device according to claim 6, in which said metal film is formed on that surface portion of said insulating film which is situated above said second region nearest to said first region.
Claim 12
Dependent Claim
14 words
A semiconductor device according to claim 2, which is of a planar, bipolar type.
Claim 13
Dependent Claim
14 words
A semiconductor device according to claim 3, which is of a planar, bipolar type.
Claim 14
Dependent Claim
14 words
A semiconductor device according to claim 5, which is of a planar, bipolar type.
Claim 15
Dependent Claim
14 words
A semiconductor device according to claim 6, which is of a planar, bipolar type.
Claim 16
Dependent Claim
14 words
A semiconductor device according to claim 9, which is of a planar, bipolar type.
References Cited (Backward Citations)
US3728166A
Cited
US3911473A
Cited
US3740621A
Cited
US4003072A
Cited
US4071852A
Cited
JPS53142878A
Cited
US4143392A
Cited
US4377029A
Cited
US4437107A
Cited
US4599638A
Cited
US4695867A
Cited
US4691223A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-31 | 1992-08-01 | 1993-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-31 | 1996-08-01 | 1997-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-31 | 2000-08-01 | 2001-01-31 | $7700.00 | Window Closed / Lapsed |