Patent US5395804A successfully refreshed from Google Patents.
US5395804A
Expired / Lapsed
US
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Method for fabricating a thin film transistor
Assignee: Sharp Corp
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Filing: 1993-03-29
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Granted: 1995-03-07
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Expires: 2013-03-29
Abstract
Abstract A method for fabricating a thin film transistor formed on an insulator is disclosed. The method includes the steps of forming a non-single crystal silicon film on the insulator, forming a polysilicon film on the insulator by thermally treating the non-single crystal silicon film in an atmosphere of a gas including hydrogen halogenide, and forming a channel region in the polysilicon film.
Inventors
- 👤 Tohru Ueda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:38
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/24; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0316; H10D30/0321; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/38; H10P14/3802; H10P14/3808; H10P14/3816; Y; Y10; Y10S; Y10S438/00; Y10S438/909
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
65 words
A method for fabricating a thin film transistor formed on an insulator, comprising the steps of: forming a non-single crystal silicon film on said insulator; forming a polysilicon film on said insulator by thermally treating said non-single crystal silicon film in an atmosphere of a gas mixture including a hydrogen halogenide gas and an oxidative gas; and forming a channel region in said polysilicon film.
Claim 2
Independent Claim
65 words
A method for fabricating a thin film transistor formed on an insulator, comprising the steps of: forming a non-single crystal silicon film on said insulator; forming a polysilicon film on said insulator by thermally treating said non-single crystal silicon film in an atmosphere of a gas mixture including a hydrogen halogenide gas and an oxidative gas; and forming a channel region in said polysilicon film.
Claim 3
Dependent Claim
15 words
A method according to claim 1, wherein said gas mixture further includes an inert gas.
Claim 4
Dependent Claim
38 words
A method according to claim 1, further comprising a step of forming a silicon oxide film on a surface of said polysilicon film by thermally treating said non-single crystal silicon film in the atmosphere of said gas mixture.
Claim 5
Dependent Claim
22 words
A method according to claim 3, further comprising a step of forming a gate insulating film made of said silicon oxide film.
Claim 6
Dependent Claim
38 words
A method according to claim 3, further comprising a step of forming a gate insulating film made of said silicon oxide film and a step of forming a gate electrode on a portion of said gate insulating film.
Claim 7
Independent Claim
67 words
A method for fabricating a thin film transistor formed on an insulator, comprising the steps of: forming a non-single crystal silicon film on said insulator; forming a silicon oxide film on said non-single crystal silicon film; forming a polysilicon film on said insulator by thermally treating said non-single crystal silicon film in an atmosphere including a hydrogen halogenide; and forming a channel region in said polysilicon film.
Claim 8
Independent Claim
67 words
A method for fabricating a thin film transistor formed on an insulator, comprising the steps of: forming a non-single crystal silicon film on said insulator; forming a silicon oxide film on said non-single crystal silicon film; forming a polysilicon film on said insulator by thermally treating said non-single crystal silicon film in an atmosphere including a hydrogen halogenide; and forming a channel region in said polysilicon film.
Claim 9
Dependent Claim
13 words
A method according to claim 6, said atmosphere further includes an inert gas.
Claim 10
Dependent Claim
22 words
A method according to claim 7, further comprising a step of forming a gate insulating film made of said silicon oxide film.
Claim 11
Dependent Claim
43 words
A method according to claim 1, wherein said step of forming said polysilicon film is performed at a temperature which is sufficiently high so that defects in said non-single crystal silicon film are repaired to some extent due to a thermal annealing effect.
Claim 12
Dependent Claim
13 words
A method according to claim 9, wherein said temperature is approximately 950° C.
Claim 13
Dependent Claim
43 words
A method according to claim 6, wherein said step of forming said polysilicon film is performed at a temperature which is sufficiently high so that defects in said non-single crystal silicon film are repaired to some extent due to a thermal annealing effect.
Claim 14
Dependent Claim
13 words
A method according to claim 11, wherein said temperature is approximately 950° C.
Claim 15
Dependent Claim
22 words
A method according to claim 6, further comprising a step of forming a gate insulating film made of said silicon oxide film.
References Cited (Backward Citations)
US4992839A
Cited
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