US5406110A
Expired / Lapsed
US
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Resurf lateral double diffused insulated gate field effect transistor
Assignee: Texas Instruments Inc
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Filing: 1994-02-01
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Granted: 1995-04-11
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Expires: 2014-02-01
Abstract
Abstract A transistor (10) has a thin epitaxial layer (14) of a second conductivity type on a semiconductor substrate (12) of a first conductivity type. A drift region (24) of the second conductivity type is formed extending through the thin epitaxial layer (14) to the substrate (12). A thick insulator layer (26) is formed on the drift region (24). An IGFET body (28) of the first conductivity type is formed adjacent the drift region (24). A source region (34) of the second conductivity type is formed within the IGFET body (28) and spaced from the drift region (24) defining a channel region (40) within the IGFET body (28). A conductive gate (32) is insulatively disposed over the IGFET body (28) and extends from the source region (34) to the thick insulator layer (26). A drain region (36) is formed adjacent the drift region (24).
Inventors
- 👤 Oh-Kyong Kwon
- 👤 Taylor R. Efland
- 👤 Satwinder Malhi
- 👤 Wai T. Ng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:36
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/028; H10D30/0281; H10D30/60; H10D30/601; H10D30/603; H10D30/64; H10D30/65; H10D62/00; H10D62/10; H10D62/13; H10D62/149; H10D62/151; H10D62/156; H10D62/157; H10D64/00; H10D64/20; H10D64/27; H10D64/311; H10D64/411; H10D64/511; H10D64/514; H10D64/516; Y; Y10; Y10S; Y10S148/00; Y10S148/096
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
175 words
A transistor formed on a semiconductor layer of a first conductivity type comprising: a thin epitaxial layer of a second conductivity type opposite said first conductivity type and formed on the semiconductor layer; a drift region of said second conductivity tape formed at a face of said thin epitaxial layer; a thick insulator layer formed on said drift region, wherein said drift region is self-aligned to margins of said thick insulator layer; a body of the first conductivity type formed at said face of said thin epitaxial layer adjacent said drift region; a source region of said second conductivity type formed at said face of said thin epitaxial layer laterally within said body, said body having a channel region between said source region and said drift region; a conductive gate insulatively disposed over said body and extending between said source region and said thick insulator layer to control conductance of said channel region; and a drain region of said second conductivity type formed at said face of said thin epitaxial layer adjacent said drift region.
Claim 2
Dependent Claim
175 words
A transistor formed on a semiconductor layer of a first conductivity type comprising: a thin epitaxial layer of a second conductivity type opposite said first conductivity type and formed on the semiconductor layer; a drift region of said second conductivity tape formed at a face of said thin epitaxial layer; a thick insulator layer formed on said drift region, wherein said drift region is self-aligned to margins of said thick insulator layer; a body of the first conductivity type formed at said face of said thin epitaxial layer adjacent said drift region; a source region of said second conductivity type formed at said face of said thin epitaxial layer laterally within said body, said body having a channel region between said source region and said drift region; a conductive gate insulatively disposed over said body and extending between said source region and said thick insulator layer to control conductance of said channel region; and a drain region of said second conductivity type formed at said face of said thin epitaxial layer adjacent said drift region.
Claim 3
Dependent Claim
20 words
The transistor of claim 1 wherein said conductive gate extends onto at least a portion of said thick insulator layer.
Claim 4
Dependent Claim
22 words
The transistor of claim 1 and further comprising a back gate connection region of the first conductivity type formed within said body.
Claim 5
Dependent Claim
15 words
The transistor of claim 3 wherein said back gate connection region adjoins said source region.
Claim 6
Dependent Claim
22 words
The transistor of claim 3 wherein a dopant concentration of said back gate connection region is higher than that of said body.
Claim 7
Dependent Claim
22 words
The transistor of claim 1 wherein a dopant concentration of said drift region is higher than that of said thin epitaxial layer.
Claim 8
Dependent Claim
21 words
The transistor of claim 1 wherein a dopant concentration of said drain region is higher than that of said drift region.
Claim 9
Dependent Claim
20 words
The transistor of claim 1 wherein a dopant concentration of said body is higher than that of the semiconductor layer.
Claim 10
Dependent Claim
18 words
The transistor of claim 1 wherein said source region and said drain region have the same dopant concentration.
Claim 11
Dependent Claim
19 words
The transistor of claim 1 wherein said drift region extends through said thin epitaxial layer to the semiconductor layer.
Claim 12
Dependent Claim
18 words
The transistor of claim 1 wherein said body extends through said thin epitaxial layer to the semiconductor layer.
Claim 13
Dependent Claim
14 words
The transistor of claim 1 wherein the first conductivity type is a (P) type.
Claim 14
Dependent Claim
25 words
The transistor of claim 1 wherein said thin epitaxial layer provides a continuous path for current flow between said drift region and said channel region.
Claim 15
Dependent Claim
26 words
The transistor of claim 1 wherein a desired breakdown voltage is selected in response to variations in dopant concentrations of said drift region and said body.
Claim 16
Dependent Claim
25 words
The transistor of claim 1 wherein a desired on-resistance is selected in response to variations in dopant concentrations of said drift region and said body.
Claim 17
Dependent Claim
19 words
The transistor of claim 1 wherein said channel region is implanted with a higher dopant concentration than said body.
Claim 18
Dependent Claim
12 words
The transistor of claim 1 wherein breakdown occurs beneath said drain region.
Claim 19
Dependent Claim
223 words
A reduced surface field lateral double diffused insulated gate field effect transistor formed on a semiconductor layer of a first conductivity type comprising: a thin epitaxial layer of a second conductivity type opposite said first conductivity type and formed on the semiconductor layer; a drift region of said second conductivity type formed at a face of said thin epitaxial layer extending through said thin epitaxial layer to the semiconductor layer and having a higher dopant concentration than said thin epitaxial layer; a thick insulator layer formed on said drift region; a body of the first conductivity type formed adjacent said drift region at said face of said thin epitaxial layer extending through said thin epitaxial layer to the semiconductor layer and having a higher dopant concentration than the semiconductor layer; a source region of said second conductivity type formed laterally within said body at said face of said thin epitaxial layer defining a channel region within said body between said source region and said drift region; a conductive gate insulatively disposed over said body extending between said source region and said thick insulator layer to control conductance of said channel region; and a drain region of said second conductivity type formed at said face of said thin epitaxial layer adjacent said drift region and having a higher dopant concentration than said drift region.
Claim 20
Dependent Claim
223 words
A reduced surface field lateral double diffused insulated gate field effect transistor formed on a semiconductor layer of a first conductivity type comprising: a thin epitaxial layer of a second conductivity type opposite said first conductivity type and formed on the semiconductor layer; a drift region of said second conductivity type formed at a face of said thin epitaxial layer extending through said thin epitaxial layer to the semiconductor layer and having a higher dopant concentration than said thin epitaxial layer; a thick insulator layer formed on said drift region; a body of the first conductivity type formed adjacent said drift region at said face of said thin epitaxial layer extending through said thin epitaxial layer to the semiconductor layer and having a higher dopant concentration than the semiconductor layer; a source region of said second conductivity type formed laterally within said body at said face of said thin epitaxial layer defining a channel region within said body between said source region and said drift region; a conductive gate insulatively disposed over said body extending between said source region and said thick insulator layer to control conductance of said channel region; and a drain region of said second conductivity type formed at said face of said thin epitaxial layer adjacent said drift region and having a higher dopant concentration than said drift region.
Claim 21
Dependent Claim
29 words
The transistor of claim 18 and further comprising a back gate connection region within said body adjacent said source region and having a higher dopant concentration than said body.
Claim 22
Dependent Claim
25 words
The transistor of claim 18 wherein said thin epitaxial layer provides a continuous path for current flow between said drift region and said channel region.
Claim 23
Dependent Claim
26 words
The transistor of claim 18 wherein a desired breakdown voltage is selected in response to variations in dopant concentrations of said drift region and said body.
Claim 24
Dependent Claim
25 words
The transistor of claim 18 wherein a desired on-resistance is selected in response to variations in dopant concentrations of said drift region and said body.
Claim 25
Dependent Claim
17 words
The transistor of claim 18 wherein said channel region has a higher dopant concentration than said body.
Claim 26
Dependent Claim
12 words
The transistor of claim 18 wherein breakdown occurs beneath said drain region.
References Cited (Backward Citations)
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