Patent EP0090661A2 successfully refreshed from Google Patents.
EP0090661A2
Expired / Lapsed
EP
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A thin film field-effect transistor and a process for producing the same
Assignee: Fujitsu Ltd
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Filing: 1983-03-30
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Granted: —
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Expires: 2003-03-30
Abstract
Abstract A thin film transistor according to the invention comprises: a glass substrate; a gate electrode which is formed on the glass substrate; a source electrode; a drain electrode; an insulating film which covers at least said gate electrode; and, an amorphous semiconductor layer which is formed on said insulating film, and which comprises a first portion having said source electrode thereon, a second portion having said drain electrode thereon, and a third portion which is between the first and second portions, is located above the gate electrode, and klwhich is thin thickness capable of permeating light of photo lithography therethrough.
Inventors
- 👤 Toshirou Kodama
- 👤 Satoru Kawai
- 👤 Yasuhiro Nasu
- 👤 Nobuyoshi Takagi
- 👤 Shintaro Yanagisawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 22:01
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0316; H10D30/0321; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6732; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6746; H10P; H10P76/00; H10P76/20; H10P76/204; H10P76/2041; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/949
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
98 words
A thin film transistor comprising: a glass substrate (11); a gate electrode (12) which is formed on said glass substrate; a source electrode (15); a drain electrode (16); an insulating film (13) which covers at least said gate electrode; characterized in that an amorphous semiconductor layer (17, 37) is formed on said insulating film, comprises a first portion having said source electrode (15) thereon, a second portion having said drain electrode (16) thereon, and a third portion which is between the first and second portions, and has a thin thickness capable of permeating light (UV) of photolithography therethrough.
Claim 2
Dependent Claim
98 words
A thin film transistor comprising: a glass substrate (11); a gate electrode (12) which is formed on said glass substrate; a source electrode (15); a drain electrode (16); an insulating film (13) which covers at least said gate electrode; characterized in that an amorphous semiconductor layer (17, 37) is formed on said insulating film, comprises a first portion having said source electrode (15) thereon, a second portion having said drain electrode (16) thereon, and a third portion which is between the first and second portions, and has a thin thickness capable of permeating light (UV) of photolithography therethrough.
Claim 3
Dependent Claim
22 words
A thin film transistor according to claim 1, wherein thickness of said amorphous semiconductor layer (17, 37) is 1,000 A or less.
Claim 4
Dependent Claim
25 words
A thin film transistor according to claim 1, wherein a passivation film (30, 40) is formed on said third portion and covers said third portion.
Claim 5
Dependent Claim
36 words
A thin film transistor according to claim 1, wherein said source electrode (15) and said drain electrode (16) are formed on portions of said amorphous semiconductor layer (17), in which portions N type impurity is doped.
Claim 6
Dependent Claim
128 words
A process for producing a thin film transistor according to claim 1, characterized in that a photoresist film (22) is formed on an amorphous semiconductor layer (17) having a thin thickness capable of permeating light of photolithography therethrough, said photoresist film (22) is selectively left only above said gate electrode (12), material (23) of source and drain electrodes (15 and 16, respectively) is deposited on the selectively left photoresist film (22) and portions of said amorphous semiconductor layer (17), said portions being exposed out of the selectively left photoresist film (22), and, said material which is deposited on the selectively left photoresist film (22) is selectively removed, thereby forming the source and drain electrodes (15 and 16, respectively) which are separated from each other via a gap therebetween.
Claim 7
Dependent Claim
30 words
A process according to claim 5, wherein a passivation film (30, 40) is formed on said amorphous semiconductor layer (37) and is selectively left only above said gate electrode (12).
Claim 8
Dependent Claim
154 words
A process for producing a thin film transistor according to claim 4, characterized in that a photoresist film (22) is formed on an amorphous semiconductor layer (17, 37) having a thin thickness capable of permeating light of photolithography therethrough, said photoresist film (22) is selectively left only above said gate electrode (12), a doped amorphous semiconductor layer is formed at a temperature of from 100 to 150°C, so that it covers the selectively left photoresist film (22) and on portions of said amorphous semiconductor layer (37), material of source and drain electrodes is deposited on said doped amorphous semiconductor layer, said material which is deposited on the selectively left photoresist film is selectively removed, thereby forming the source and drain electrodes (15 and 16, respectively) which are separated from each other via a gap therebetween, and an impurity of said doped amorphous semiconductor layer is activated at a temperature of from 250 to 350°C.
References Cited (Backward Citations)
No citation records indexed.
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