Claims
- 1. A process for producing a thin film transistor having a glass substrate, comprising the steps of:
- (a) forming a gate electrode on the glass substrate;
- (b) forming an insulating film on at least the gate electrode;
- (c) forming an amorphous semiconductor layer having a thickness which allows photolithographic light to permeate therethrough;
- (d) forming a positive photoresist film on the amorphous semiconductor layer;
- (e) selectively exposing the photoresist film from underneath the glass substrate so that it remains only above the gate electrode;
- (f) depositing source and drain electrode material on the remaining photoresist film and on portions of the amorphous semiconductor layer not covered by the remaining photoresist film; and
- (g) selectively removing the electrode material which is deposited on the remaining photoresist film, thereby forming source and drain electrodes separated from each other by a gap formed therebetween.
- 2. A process according to claim 1, wherein said steps (b) and (c) comprise consecutively forming the insulating film and the amorphous semiconductor layer by means of a plasma CVD process.
- 3. A process according to claim 1, wherein the plasma CVD process includes the step of maintaining a predetermined degree of vacuum.
- 4. A process for producing a thin film transistor having a glass substrate, comprising the steps of:
- (a) forming a gate electrode on the glass substrate;
- (b) forming an insulating film which covers at least the gate electrode;
- (c) forming an amorphous semiconductor layer on the insulating layer, having a thickness which allows photolithographic light to permeate therethrough;
- (d) forming a passivation film on the amorphous semiconductor layer, the amorphous semiconductor layer and the passivation film being consecutively formed;
- (e) forming a positive photoresist on the passivation film;
- (f) selectively exposing the photoresist film from underneath the glass substrate so that it remains only above the gate electrode;
- (g) selectively removing the passivation film by using the remaining photoresist film as a mask;
- (h) depositing source and drain electrode material on the remaining photoresist film and on portions of the passivation film; and
- (i) selectively removing the electrode material deposited on the remaining photoresist film, thereby forming source and drain electrodes.
- 5. A process for producing a thin film transistor according to claim 4, wherein said step (c) comprises forming the amorphous semiconductor layer to a thickness of from 50 .ANG. to 1000 .ANG..
- 6. A process or producing a thin film transistor having a glass substrate, comprising the steps of:
- (a) forming a gate electrode on the glass substrate;
- (b) forming an insulating film which covers at least the gate electrode;
- (c) forming an amorphous semiconductor layer on the insulating film, having a thickness which allows photolithographic light to permeate therethrough;
- (d) forming a positive photoresist film on the amorphous semiconductor layer;
- (e) selectively exposing the photoresist film from underneath the glass substrate so that it remains only above the gate electrode;
- (f) forming a doped amorphous semiconductor layer, at a temperature of from 100.degree. C. to 150.degree. C., on the remaining photoresist film and portions of the amorphous semiconductor layer;
- (g) depositing source and drain electrode material on the doped amorphous semiconductor layer;
- (h) selectively removing the source and drain electrode material deposited on the remaining photoresist film, thereby forming source and drain electrodes which are separated from each other by a gap therebetween; and
- (i) activating an impurity contained in the doped amorphous semiconductor layer by applying a temperature of from 250.degree. C. to 350.degree. C.
- 7. A process for producing a thin film transistor according to claim 6, wherein said step (f) comprises forming the doped amorphous semiconductor layer having a N-type impurity.
- 8. A process for producing a thin film transistor according to claim 6, wherein said step (a) comprises forming the gate electrode to a thickness of approximately 0.1 .mu.m.
- 9. A process for producing a thin film transistor according to claim 6, wherein said step (b) comprises forming the insulating film to a thickness of approximately 0.3 .mu.m.
- 10. A process for producing a thin film transistor according to claim 6, wherein said step (c) comprises forming the amorphous semiconductor layer to a thickness of form 50 .ANG. to 1000 .ANG..
Priority Claims (1)
Number |
Date |
Country |
Kind |
57-53239 |
Mar 1982 |
JPX |
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Parent Case Info
This is a continuation of copending application Ser. No. 07/302,996 filed on Jan. 27, 1989, now abandoned, which is a continuation of Ser. No. 07/198,581, filed on May 2, 1988, abandoned; which is a continuation of Ser. No. 06/883,022, filed 7/9/86, abandoned; which is a division of Ser. No. 06/824,319, filed 1/31/86, abandoned; and which is a continuation of Ser. No. 06/480,579, filed 3/30/83abandoned.
US Referenced Citations (14)
Foreign Referenced Citations (2)
Number |
Date |
Country |
071244A |
Feb 1983 |
EPX |
0113666 |
Jun 1984 |
JPX |
Non-Patent Literature Citations (8)
Entry |
Staebler et al., "Conductivity Changes in Dehydrogenated and Rehydrogenated Discharge-Produced A-Si:H", Appl. Phys. Lett., 37(7) Oct. 1980, pp. 609-612. |
Snell et al., "Application of Amorphous Silicon Field Effect Transistor in Addressable Liquid Crystal Display Panels", Appl. Physics 24 (1981) pp. 357-362. |
Fang, "TFT Structure with Electronically Adjustable Threshold", IBM Technical Disclosure Bulletin, vol. 20, No. 12, May 1978, pp. 5352. |
Hayama et al., "Amorphous-Silicon Thin-Film Metal-Oxide-Semiconductor Transistors" Appl. Phys. Letts. 36(9), May 1, 1980 pp. 454-455. |
Weimer, "The TFT-A New Thin-Film Transistor", Proceedings of the IEEE, Jun. 1962, pp. 1462-1469. |
SID 82 Digest, "Large-Scale LCDs Addressed by a-Si TFT Array", Okubo et al., pp. 40-43. |
Hayama, Appl. Phys. Lett. 36(9), May 1, 1980. |
Weimer Proceedings of the IEEE, Jun. 1962 p. 1462 et seq. |
Divisions (1)
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Number |
Date |
Country |
Parent |
824319 |
Jan 1986 |
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Continuations (4)
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Number |
Date |
Country |
Parent |
302996 |
Jan 1989 |
|
Parent |
198581 |
May 1988 |
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Parent |
883022 |
Jul 1986 |
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Parent |
480579 |
Mar 1983 |
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