EP0146181A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor device comprising a combined bipolar-field effect transistor
Assignee: Koninklijke Philips NV
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Filing: 1984-12-05
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Granted: —
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Expires: 2004-12-05
Abstract
Abstract A combined bipolar-field effect transistor RESURF device includes a lightly-doped epitaxial buried layer (16) of a first conductivity type located between a semiconductor substrate (11) of the first conductivity type and an epitaxial surface layer (18) of a second conductivity type opposite to that of the first. The doping concentration and thickness of the epitaxial surface layer (18) are selected in accordance with the REduced SURface Field (RESURF) technique. A highly-doped buried layer (14) of the first conductivity type may be provided in the substrate (11) where it meets the lightly-doped epitaxial buried layer (16). A highly-doped buried region (19) of the second conductivity type may be located beneath the base region (20) of the device and sandwiched between the epitaxial buried layer (16) and the epitaxial surface layer (18). The advantages of such a device include a substantially reduced «on» resistance, a more compact and flexible configuration, improved switching characteristics, reduced base device current requirements, and improved isolation. The device may be further improved by providing a buried annular region (21) of the first conductivity type around and in contact with said buried region (19), and a surface adjoining annular region (23) of the first conductivity may be provided adjacent the base region (20).
Inventors
- 👤 Barry Mana Singer
- 👤 Edward Henry Stupp
- 👤 Rajsekhar Yayaraman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 12:12
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/64; H10D30/65; H10D12/00; H10D12/411; H10D62/00; H10D62/10; H10D62/102; H10D62/103; H10D62/105; H10D62/106; H10D84/00; H10D84/101; H10D84/121; H10D84/40; H10D84/401; H10D84/403; H10D84/406; H10W; H10W15/00; H10W15/01; H10D62/13; H10D62/149; H10D62/151; H10D62/156; H10D62/157; H10D62/17; H10D62/351; H10D62/357; H10D62/364; H10D62/371
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
284 words
A combined bipolar-field effect transistor RESURF device, comprising A semiconductor substrate of a first conductivity type and having a major surface and a substrate electrode connected to the side of said substrate opposite said major surface, an epitaxial surface layer of a second conductivity type opposite to that of said first conductivity type, the doping concentration and thickness of said epitaxial surface layer being selected in accordance with the REduced SURface Field (RESURF) technique, a surface-adjoining base region of said first conductivity type in said epitaxial surface layer, a base electrode connected to said base region, a surface-adjoining source/emitter region of said second conductivity type in said base region, the source/emitter region serving both as the source and the emitter of said combined device, a source/emitter electrode connected to said source/emitter region, a surface-adjoining drain/collector region of said second conductivity type in said epitaxial surface layer and spaced apart from said base region, the drain/collector region serving as both the drain and the collector of said canbined device, a drain ¡collector electrode connected to said drain/collector region, a surface-adjoining channel region at least partly in that portion of said base region which is adjacent said drain/collector region, an insulating layer on said surface layer and covering at least that part of said channel region which is in said base region and a gate electrode on said insulating layer and over at least that part of said channel region which is in said base region, characterized in that the device comprises a lightly-doped epitaxial buried layer of said first conductivity type on said major surface of the substrate and having a doping level at least an order of magnitude less than that of said substrate.
Claim 2
Dependent Claim
284 words
A combined bipolar-field effect transistor RESURF device, comprising A semiconductor substrate of a first conductivity type and having a major surface and a substrate electrode connected to the side of said substrate opposite said major surface, an epitaxial surface layer of a second conductivity type opposite to that of said first conductivity type, the doping concentration and thickness of said epitaxial surface layer being selected in accordance with the REduced SURface Field (RESURF) technique, a surface-adjoining base region of said first conductivity type in said epitaxial surface layer, a base electrode connected to said base region, a surface-adjoining source/emitter region of said second conductivity type in said base region, the source/emitter region serving both as the source and the emitter of said combined device, a source/emitter electrode connected to said source/emitter region, a surface-adjoining drain/collector region of said second conductivity type in said epitaxial surface layer and spaced apart from said base region, the drain/collector region serving as both the drain and the collector of said canbined device, a drain ¡collector electrode connected to said drain/collector region, a surface-adjoining channel region at least partly in that portion of said base region which is adjacent said drain/collector region, an insulating layer on said surface layer and covering at least that part of said channel region which is in said base region and a gate electrode on said insulating layer and over at least that part of said channel region which is in said base region, characterized in that the device comprises a lightly-doped epitaxial buried layer of said first conductivity type on said major surface of the substrate and having a doping level at least an order of magnitude less than that of said substrate.
Claim 3
Dependent Claim
43 words
A combined bipolar-field effect transistor RESURF device as claimed in claim 1, characterized in that said lightly-doped epitaxial buried layer is of P conductivity type and has a doping level of about 3x10 14 atoms/cm 3 and a thickness of about 30 microns.
Claim 4
Dependent Claim
48 words
A combined bipolar-field effect transistor RESURF device as claimed in claim 1, characterized in that a highly-doped buried layer of said first conductivity type is present in said substrate at said major surface, the doping level of said highly-doped buried layer being greater than that of said substrate.
Claim 5
Dependent Claim
57 words
A combined bipolar-field effect transistor RESURF device as claimed in anyone of the preceding claims, characterized in that the device comprises a highly-doped buried region of said second conductivity type located beneath said base region and sandwiched between said epitaxial buried layer of the first conductivity type and said epitaxial surface layer of the second conductivity type.
Claim 6
Dependent Claim
51 words
A combined bipolar-field effect transistor RESURF device as claimed in claim 4, characterized in that said highly-doped buried region is of n+ conductivity type and has a doping level in the range of about 10 18 - 10 20 atoms/cm 3 and a thickness in the range of about 1-2 microns.
Claim 7
Dependent Claim
45 words
A combined bipolar-field effect transistor RESURF device as claimed in claims 2, 3 and 5, characterized in that said highly-doped buried layer is of p conductivity type and has a doping level of about 10 18 atoms/cm 3 and a thickness of about 5 microns.
Claim 8
Dependent Claim
46 words
A combined bipolar-field effect transistor RESURF device as claimed in anyone of claims 4, 5 or 6, characterized in that the device comprises a buried annular region of said first conductivity type around and in contact with the highly-doped buried region of said second conductivity type.
Claim 9
Dependent Claim
50 words
A combined bipolar-field effect transistor RESURF device as claimed in claim 7, characterized in that said buried annular region is of p conductivity type and has a doping level in the range of about 3x10 15 - 1x10 16 atoms/cm and a thickness in the range of about 1-2 microns.
Claim 10
Dependent Claim
27 words
A combined bipolar field effect transistor RESURF device as in claim 7, further comprising a surface-adjoining annular region of said first conductivity type adjacent said base region.
Claim 11
Dependent Claim
39 words
A combined bipolar-field effect transistor RESURF device as in claim 9, wherein said surface-adjoining annular region is of p conductivity type and has a doping level of about 10 16 atoms/cm 3 and a thickness of about 1 micron.
References Cited (Backward Citations)
No citation records indexed.
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