EP0179407A2
Expired / Lapsed
EP
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Method for producing a DMOS semiconductor device
Assignee: STMicroelectronics SRL
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Filing: 1985-10-18
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Granted: —
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Expires: 2005-10-18
Abstract
Abstract An improved method for the fabrication of a DMOS transistor. The method comprises forming the source region of the transistor by introducing doping from a doped, thin polycrystalline layer. A thin insulating layer is used to protect the body channel contact region, from the source doping, and the thin polycrystalline layer is completely consumed and converted into an insulator by oxidation subsequent to the source doping step.
Inventors
- 👤 Claudio Contiero
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 14:48
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/028; H10D30/0291; H10P; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/1414; H10P32/17; H10P32/171
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
48 words
A method for the fabrication of a DMOS transistor wherein said DMOS transistor comprises a body channel region and at least one source region located in a substrate, characterized by the steps of doping and forming said source region from a doped polycrystalline layer deposited on said substrate.
Claim 2
Independent Claim
48 words
A method for the fabrication of a DMOS transistor wherein said DMOS transistor comprises a body channel region and at least one source region located in a substrate, characterized by the steps of doping and forming said source region from a doped polycrystalline layer deposited on said substrate.
Claim 3
Dependent Claim
38 words
A method according to claim 1, characterized in that said doped polycrystalline layer is a thin polycrystalline silicon layer, further comprising the step of completely oxidizing said doped polycrystalline layer following said source region doping and forming step.
Claim 4
Dependent Claim
98 words
A method according to claim 1, said DMOS transistor comprising a body channel region, a body channel contact region, at least one source region, a gate electrode, and a gate insulator, characterized by the steps of: forming said body channel contact region; forming said body channel region; protecting at least a portion of said body channel region with an insulator; depositing a thin layer of doped polycrystalline silicon to contact at least a portion of said body channel contact region that is unprotected by said insulator; and forming said source region by doping from said doped polycrystalline silicon.
Claim 5
Dependent Claim
34 words
A method according to claim 3, characterized in that said insulator protecting step comprises the step of forming a silicon dioxide layer followed by the step of forming openings in said silicon dioxide layer.
Claim 6
Dependent Claim
26 words
A method according to claim 3 or 4 further including the step of completely oxidizing said thin layer of polycrystalline silicon when forming said source region.
Claim 7
Dependent Claim
38 words
A method according to claim 3,4 or 5 characterized in that said thin,layer of polycrystalline silicon is doped with arsenic, said source region being a N type conductivity, and said DMOS transistor being an N channel DMOS transistor.
Claim 8
Dependent Claim
27 words
A method according to claim 3,4,5 or 6 characterized in that said step of forming said body channel region comprises ion implantation through a gate insulating layer.
Claim 9
Dependent Claim
35 words
A method according to claim 7, characterized in that said step of protecting a portion of said body channel region comprises leaving a portion of said gate insulating layer over said body channel contact region.
Claim 10
Dependent Claim
39 words
A method according to claim 5, further including the step of forming an opening through said oxidized polycrystalline silicon layer to expose at least a portion of said source region and a portion of said body channel contact region.
Claim 11
Dependent Claim
34 words
A method according to claim 9, further including the step of depositing an electrically conducting material into said opening for electrically contacting and electrically shorting said source region to said body channel contact region.
Claim 12
Dependent Claim
13 words
A DMOS transistor device, obtainable by the method according to any claims 1-10.
References Cited (Backward Citations)
No citation records indexed.
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