Patent US5200632A successfully refreshed from Google Patents.
US5200632A
Expired / Lapsed
US
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Conductivity modulation mosfet
Assignee: Fuji Electric Co Ltd
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Filing: 1991-04-18
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Granted: 1993-04-06
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Expires: 2011-04-18
Abstract
Abstract A conductivity modulation type MOSFET including a first region of a first conductivity type having a low impurity concentration, second regions of a second conductivity type selectively formed on the surface region of one side of the first region, third regions of the first conductivity type selectively formed on the surface region of the second regions, gate electrodes each formed above the surface region of the second region located between the first region and the third region, a plurality of gate insulating films interlayered between the gate electrodes and the surface region of the second regions, an emitter electrode in contact with both the second regions and the third regions, a fourth region of the second conductivity type having a high impurity concentration, formed adjoining to another side of the first region, fifth regions of the second conductivity type, selectively formed surrounding the fourth region, having a lower impurity concentration than that of the fourth region, and a collector electrode being in contact with both the fourth region and the fifth regions.
Inventors
- 👤 Kenya Sakurai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:52
CPC Classifications
H; H10; H10D; H10D12/00; H10D12/01; H10D12/031; H10D12/032; H10D12/411; H10D12/441
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
183 words
A conductivity modulation type MOSFET comprising: a first region of a first conductivity type having a low impurity concentration; a plurality of second regions of a second conductivity type selectively formed in a surface region of one side of the first region; a plurality of third regions of the first conductivity type selectively formed in a surface region of the second regions; a plurality of gate electrodes each formed above a surface region of the second region located between the first region and the third region; a gate insulating film between the gate electrode and the surface region of the second region; an emitter electrode in contact with both the second region and the third region; a fourth region of the second conductivity type having a high impurity concentration, formed adjoining an other side of the first region; a plurality of fifth regions of the second conductivity type, selectively formed surrounding the fourth region to have a lower impurity concentration than the inpurity concentration of the fourth region; and a collector electrode in contact with both the fourth region and the fifth regions.
Claim 2
Dependent Claim
183 words
A conductivity modulation type MOSFET comprising: a first region of a first conductivity type having a low impurity concentration; a plurality of second regions of a second conductivity type selectively formed in a surface region of one side of the first region; a plurality of third regions of the first conductivity type selectively formed in a surface region of the second regions; a plurality of gate electrodes each formed above a surface region of the second region located between the first region and the third region; a gate insulating film between the gate electrode and the surface region of the second region; an emitter electrode in contact with both the second region and the third region; a fourth region of the second conductivity type having a high impurity concentration, formed adjoining an other side of the first region; a plurality of fifth regions of the second conductivity type, selectively formed surrounding the fourth region to have a lower impurity concentration than the inpurity concentration of the fourth region; and a collector electrode in contact with both the fourth region and the fifth regions.
Claim 3
Dependent Claim
44 words
A conductivity modulation type MOSFET according to claim 1, further comprising a plurality of sixth regions of the first conductivity type, formed between the fourth regions and surrounded by the fifth regions to have a higher impurity concentration than that of the first region.
Claim 4
Dependent Claim
32 words
A conductivity modulation type MOSFET according to claim 1, wherein the low impurity concentration is about 10 15 cm -3 and the high impurity concentration is about 10 18 cm -3 .
Claim 5
Dependent Claim
221 words
A conductivity modulation type MOSFET comprising: a first region of a first conductivity type having a low impurity concentration; a plurality of second regions of a second conductivity type selectively formed in a surface region of one side of the first region; a plurality of third regions of the first conductivity type selectively formed in a surface region of the second regions; a plurality of gate electrodes each formed above a surface region of the second region located between the first region and the third region; a gate insulating film between the gate electrode and the surface region of the second region; an emitter electrode in contact with both the second region and the third region; a fourth region of the first conductivity type, formed adjoining to another side of the first region and having a lower impurity concentration than the impurity concentration of the first region; a plurality of fifth regions, selectively formed in the fourth region and having a higher impurity concentration than the impurity concentration of the fourth region; a sixth region of the second conductivity type adjoining sides of the fourth region and the fifth regions, opposite the first region, the impurity concentration of the sixth region being lower than the impurity concentration of the fifth region; and a collector electrode in contact with the sixth region.
Claim 6
Dependent Claim
221 words
A conductivity modulation type MOSFET comprising: a first region of a first conductivity type having a low impurity concentration; a plurality of second regions of a second conductivity type selectively formed in a surface region of one side of the first region; a plurality of third regions of the first conductivity type selectively formed in a surface region of the second regions; a plurality of gate electrodes each formed above a surface region of the second region located between the first region and the third region; a gate insulating film between the gate electrode and the surface region of the second region; an emitter electrode in contact with both the second region and the third region; a fourth region of the first conductivity type, formed adjoining to another side of the first region and having a lower impurity concentration than the impurity concentration of the first region; a plurality of fifth regions, selectively formed in the fourth region and having a higher impurity concentration than the impurity concentration of the fourth region; a sixth region of the second conductivity type adjoining sides of the fourth region and the fifth regions, opposite the first region, the impurity concentration of the sixth region being lower than the impurity concentration of the fifth region; and a collector electrode in contact with the sixth region.
Claim 7
Dependent Claim
21 words
A conductivity modulation type MOSFET according to claim 4, wherein the low impurity concentration is about 10 15 cm -3 .
References Cited (Backward Citations)
US4292646A
Cited
US4587547A
Cited
US4689647A
Cited
US4617583A
Cited
JPS61208268A
Cited
US4841345A
Cited
US4918509A
Cited
US4888627A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-04-05 | 1996-10-05 | 1997-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-05 | 2000-10-05 | 2001-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-05 | 2004-10-05 | 2005-04-06 | $7700.00 | Window Closed / Lapsed |