US5153146A
Expired / Lapsed
US
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Maufacturing method of semiconductor devices
Assignee: Toshiba Corp
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Filing: 1991-05-24
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Granted: 1992-10-06
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Expires: 2011-05-24
Abstract
Abstract Formed on the element region of an n-type semiconductor substrate is a silicon oxide layer, on which a polysilicon layer is formed. Boron ions, p-type impurities, are then implanted into the polysilicon layer, from which boron diffuses into the element region via the silicon oxide layer, with the result that a p-channel region of the p-channel MOS transistor is formed.
Inventors
- 👤 Yoshiaki Toyoshima
- 👤 Tamao Eguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:28
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0223; H10D30/60; H10D30/637; H10D62/00; H10D62/10; H10D62/17; H10D62/213; H10D62/221; H10D62/235; H10P; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/141; H10P32/1412; H10P32/17; H10P32/171; Y; Y10; Y10S; Y10S438/00; Y10S438/914; Y10S438/923
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
142 words
A method for manufacturing semiconductor devices, comprising: a first step of forming a first gate oxide layer on an element region of a semiconductor substrate of a first conductivity type; a second step of forming a first polysilicon layer on said first gate oxide layer; a third step of introducing into said first polysilicon layer impurities of a second conductivity type opposite in polarity to the first conductivity type; a fourth step of diffusing impurities of the second conductivity type from said first polysilicon layer, into which said second conductivity-type impurities have been introduced, to said element region, said fourth step being effected by heat treatment; and a fifth step of changing the conductivity type of said first polysilicon layer by diffusing impurities of the first conductivity type into said first polysilicon layer, to which said second conductivity-type impurities have been introduced.
Claim 2
Independent Claim
142 words
A method for manufacturing semiconductor devices, comprising: a first step of forming a first gate oxide layer on an element region of a semiconductor substrate of a first conductivity type; a second step of forming a first polysilicon layer on said first gate oxide layer; a third step of introducing into said first polysilicon layer impurities of a second conductivity type opposite in polarity to the first conductivity type; a fourth step of diffusing impurities of the second conductivity type from said first polysilicon layer, into which said second conductivity-type impurities have been introduced, to said element region, said fourth step being effected by heat treatment; and a fifth step of changing the conductivity type of said first polysilicon layer by diffusing impurities of the first conductivity type into said first polysilicon layer, to which said second conductivity-type impurities have been introduced.
Claim 3
Dependent Claim
19 words
A method for manufacturing semiconductor devices according to claim 1, wherein said third step is effected by ion implantation.
Claim 4
Dependent Claim
34 words
A method for manufacturing semiconductor devices according to claim 1, wherein said fourth step is effected by said diffusing being performed by heat treatment in an atmosphere of a gas containing hydrogen or water.
Claim 5
Dependent Claim
21 words
A method for manufacturing semiconductor devices according to claim 1, wherein said third step is effected by ion implantation of boron.
Claim 6
Dependent Claim
26 words
A method for manufacturing semiconductor devices according to claim 4, wherein said ion implantation is performed at an ion accelerating voltage of 40 KeV or below.
Claim 7
Dependent Claim
29 words
A method for manufacturing semiconductor devices according to claim 1, further comprising, after the fifth step, a sixth step of patterning said first polysilicon layer to a desired shape.
Claim 8
Dependent Claim
42 words
A method for manufacturing semiconductor devices according to claim 6, further comprising a seventh step of forming source and drain regions by introducing impurities of the second conductivity type into said substrate with said desired-shaped first polysilicon layer serving as a mask.
Claim 9
Independent Claim
184 words
A method for manufacturing semiconductor devices, comprising: a first step of forming gate oxide layer on an element region of a semiconductor substrate of a first conductivity type; a second step of forming a first polysilicon layer on said first gate oxide layer; a third step of introducing into said first polysilicon layer impurities of a second conductivity type opposite in polarity to the first conductivity type; a fourth step of diffusing impurities of the second conductivity type from said first polysilicon layer, into which said second conductivity-type impurities have been introduced, to said element region, said fourth step being achieved by heat treatment in an atmosphere of gas containing hydrogen or water; a fifth step of removing said first polysilicon layer and said first oxide layer in sequence; a sixth step of forming a second gate oxide layer on said element region; a seventh step of forming a second polysilicon layer on at least said gate oxide layer; and an eighth step of adding to said second polysilicon layer impurities of a second conductivity type opposite in polarity to said first conductivity type.
Claim 10
Independent Claim
184 words
A method for manufacturing semiconductor devices, comprising: a first step of forming gate oxide layer on an element region of a semiconductor substrate of a first conductivity type; a second step of forming a first polysilicon layer on said first gate oxide layer; a third step of introducing into said first polysilicon layer impurities of a second conductivity type opposite in polarity to the first conductivity type; a fourth step of diffusing impurities of the second conductivity type from said first polysilicon layer, into which said second conductivity-type impurities have been introduced, to said element region, said fourth step being achieved by heat treatment in an atmosphere of gas containing hydrogen or water; a fifth step of removing said first polysilicon layer and said first oxide layer in sequence; a sixth step of forming a second gate oxide layer on said element region; a seventh step of forming a second polysilicon layer on at least said gate oxide layer; and an eighth step of adding to said second polysilicon layer impurities of a second conductivity type opposite in polarity to said first conductivity type.
Claim 11
Dependent Claim
29 words
A method for manufacturing semiconductor devices according to claim 8, further comprising, after the eighth step, a ninth step of patterning said second polysilicon layer to a desired shape.
Claim 12
Dependent Claim
42 words
A method for manufacturing semiconductor devices according to claim 9, further comprising a tenth step of forming source and drain regions by introducing impurities of the second conductivity type into said substrate with said desired-shaped second polysilicon layer serving as a mask.
References Cited (Backward Citations)
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