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US4864379A Expired / Lapsed US ⏱️ 0.0 years remaining

Bipolar transistor with field shields

Assignee: Intersil Corp
•
Filing: 1988-05-20
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Granted: 1989-09-05
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Expires: 2008-05-20
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Abstract

Abstract A bipolar transistor includes a substrate of semiconductor material having an expitaxial body of the semiconductor material on a surface thereof. The semiconductor body has a major surface. A collector region of one conductivity type is in the body at the major surface and a base region of the opposite conductivity type is in the collector region at the major surface and forms with the collector region a collector/base junction which extends to the surface. A plurality of emitter regions of the one conductivity type are in the base region and form with the base region emitter/base junctions which extend to the surface. At least some of the emitter/base junctions are adjacent to but spaced from the collector/base junction at the major surface. A layer of insulating silicon oxide is on the major surface and a layer of conductive polysilicon is on the insulating layer. The polysilicon layer includes strips which extend only over the area of the surface between the collector/base junction and the adjacent emitter/base junctions and resistor areas to which the strips are connected. The emitter regions are connected to the polysilicon layer. The bipolar transistor may be part of an integrated circuit which includes MOS transistors and the polysilicon layer also forms the gates of the MOS transistors.

Inventors

  • 👤 Otto H. Schade, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:44
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/111; H10D62/00; H10D62/10; H10D62/13; H10D62/133; H10D62/135; H10D84/00; H10D84/101; H10D84/121; H10D84/125; H10D84/40; H10D84/401

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 117 words
A bipolar transistor comprising: a body of a semiconductor material having a major surface; a first region of one conductivity type in said body and at said surface; a second region of the opposite conductivity type in said first region at said surface; a third region of the one conductivity type in said second region with a junction between the third region and the second region being spaced from a junction between the second region and the first region; and a layer of conductive polycrystalline silicon over and insulated from said surface of the body and having strip portions extending only over the entire area of the surface between said junctions to serve as a field shield.
Claim 2
Dependent Claim 117 words
A bipolar transistor comprising: a body of a semiconductor material having a major surface; a first region of one conductivity type in said body and at said surface; a second region of the opposite conductivity type in said first region at said surface; a third region of the one conductivity type in said second region with a junction between the third region and the second region being spaced from a junction between the second region and the first region; and a layer of conductive polycrystalline silicon over and insulated from said surface of the body and having strip portions extending only over the entire area of the surface between said junctions to serve as a field shield.
Claim 3
Dependent Claim 21 words
A bipolar transistor in accordance with claim I wherein the layer of conductive polycrystalline silicon includes an area forming a resistor.
Claim 4
Dependent Claim 32 words
A bipolar transistor in accordance with claim 2 including a layer of insulating silicon oxide over the major surface of the body and the polycrystalline silicon layer is on the insulating layer.
Claim 5
Dependent Claim 70 words
A bipolar transistor in accordance with claim 3 including a plurality of spaced third regions in said second region forming the emitter of said transistor with some of said third regions having their junctions with the second region being adjacent to but spaced from the junction between the second and first regions, and the strips of the polycrystalline silicon extend over the area of said major surface between said junctions.
Claim 6
Dependent Claim 19 words
A bipolar transistor in accordance with claim 4 in which the third regions are arranged in rows and columns.
Claim 7
Dependent Claim 43 words
A bipolar transistor in accordance with claim 5 including contact regions of the same conductivity type as the second region but more highly conductive than the second region, said contact regions being in the second region between the columns of the third regions.
Claim 8
Dependent Claim 34 words
A bipolar transistor in accordance with claim 6 in which the resistor areas are substantially rectangular areas of the polycrystalline silicon layer with the strips being connected to an end of the resistor areas.
Claim 9
Dependent Claim 26 words
A bipolar transistor in accordance with claim 7 in which the resistor areas, include notches in opposite edges thereof to adjust the resistance of the resistors.
Claim 10
Dependent Claim 65 words
A bipolar transistor in accordance with claim 8 including a layer of insulating silicon oxide over the polycrystalline silicon layer and conductors over the silicon oxide layer, said conductors extending through openings in the silicon oxide layers with some of the conductors making ohmic contact to the third regions and some of the conductors making ohmic contact to the contact regions of the second region
Claim 11
Dependent Claim 28 words
A bipolar transistor in accordance with claim 9 in which the contacts which make ohmic contact to the third region also make ohmic contact to the resistor areas.
Claim 12
Dependent Claim 191 words
A bipolar transistor comprising: a substrate of single crystalline silicon; an epitaxial body of single crystalline silicon on said substrate and having a major surface; a collector region of one conductivity type in said body at said major surface; a base region of the opposite conductivity type in the collector region at said major surface and forming with the collector region a collector/base junction which extends to said major surface; a plurality of emitter regions of the one conductivity type in said base region at said major surface, each of said emitter regions forming with the base region emitter/base junctions which extend to said major surface with some of the emitter/base junctions being adjacent to but spaced from the collector/base junction at the major surface; a layer of insulating silicon oxide on said major surface; a layer of conductive polycrystalline silicon on said insulating layer, said polycrystalline silicon layer having strips which extend over only the entire area of the major surface between the collector/base junction and the adjacent emitter/base junctions and having resistor areas to which the strips are connected; and means connecting the polycrystalline silicon layer to the emitters.
Claim 13
Dependent Claim 191 words
A bipolar transistor comprising: a substrate of single crystalline silicon; an epitaxial body of single crystalline silicon on said substrate and having a major surface; a collector region of one conductivity type in said body at said major surface; a base region of the opposite conductivity type in the collector region at said major surface and forming with the collector region a collector/base junction which extends to said major surface; a plurality of emitter regions of the one conductivity type in said base region at said major surface, each of said emitter regions forming with the base region emitter/base junctions which extend to said major surface with some of the emitter/base junctions being adjacent to but spaced from the collector/base junction at the major surface; a layer of insulating silicon oxide on said major surface; a layer of conductive polycrystalline silicon on said insulating layer, said polycrystalline silicon layer having strips which extend over only the entire area of the major surface between the collector/base junction and the adjacent emitter/base junctions and having resistor areas to which the strips are connected; and means connecting the polycrystalline silicon layer to the emitters.

References Cited (Backward Citations)

US3911473A Cited
US4423433A Cited
US4298402A Cited
US4437107A Cited
US4430663A Cited
US4656496A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-09-04 1993-03-06 1993-09-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-09-04 1997-03-06 1997-09-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-09-04 2001-03-06 2001-09-05 $7700.00 Window Closed / Lapsed

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