US4956680A
Expired / Lapsed
US
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Thin film transistor
Assignee: LG Display Co Ltd
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Filing: 1987-12-14
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Granted: 1990-09-11
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Expires: 2007-12-14
Abstract
Abstract A thin film transistor having a shading layer for reducing optical leakage current. The shading layer is made essentially of opaque organic material.
Inventors
- 👤 Hideo Tanaka
- 👤 Shunichi Motte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:19
CPC Classifications
H; H10; H10D; H10D86/00; H10D30/00; H10D30/60; H10D30/67; H10D30/6704; H10D30/6723
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
92 words
A thin film transistor comprising: an insulating substrate, a gate electrode disposed on the insulating substrate, a gate insulating film disposed on the gate electrode and the insulating substrate, an amorphous semiconductor film disposed on the gate insulating film, a source electrode and a drain electrode disposed in spaced relation to each other on the amorphous semiconductor film, and a light-shielding film disposed on the source electrode, the drain electrode and the amorphous semiconductor film for reducing optical leakage current, the light-shielding film being composed essentially of photoresist material containing black carbon.
Claim 2
Dependent Claim
92 words
A thin film transistor comprising: an insulating substrate, a gate electrode disposed on the insulating substrate, a gate insulating film disposed on the gate electrode and the insulating substrate, an amorphous semiconductor film disposed on the gate insulating film, a source electrode and a drain electrode disposed in spaced relation to each other on the amorphous semiconductor film, and a light-shielding film disposed on the source electrode, the drain electrode and the amorphous semiconductor film for reducing optical leakage current, the light-shielding film being composed essentially of photoresist material containing black carbon.
Claim 3
Dependent Claim
21 words
A thin film transistor according to claim 1; wherein the amorphous semiconductor film has a thickness of 0.02 to 0.3 μm.
Claim 4
Dependent Claim
28 words
A thin film transistor according to claim 1; wherein the source electrode and the drain electrode are disposed on the amorphous semiconductor film through respective ohmic contact layers.
Claim 5
Dependent Claim
21 words
A thin film transistor according to claim 3; wherein each of the ohmic contact layers comprises an N-type hydrogenated amorphous silicon.
Claim 6
Dependent Claim
22 words
A thin film transistor according to claim 3; wherein each of the ohmic contact layers comprises an N-type hydrogenated fine crystalline silicon.
Claim 7
Dependent Claim
23 words
A thin film transistor according to claim 3; wherein each of the ohmic contact layers has a thickness of 0.005 to 0.02 μm.
Claim 8
Dependent Claim
105 words
A thin film transistor comprising: an insulating substrate; a gate electrode disposed on the insulating substrate; a gate insulating film disposed on the gate electrode and the insulating substrate; an amorphous semiconductor film disposed on the gate insulating film; two ohmic contact layers disposed in spaced relation to each other on the amorphous semiconductor layer; a source electrode and a drain electrode disposed on the respective ohmic contact layers; and an opaque organic light-shielding film disposed on the source electrode, the drain electrode and the amorphous semiconductor film for reducing optical leakage current, the light-shielding film being composed essentially of photoresist material containing black carbon.
Claim 9
Dependent Claim
105 words
A thin film transistor comprising: an insulating substrate; a gate electrode disposed on the insulating substrate; a gate insulating film disposed on the gate electrode and the insulating substrate; an amorphous semiconductor film disposed on the gate insulating film; two ohmic contact layers disposed in spaced relation to each other on the amorphous semiconductor layer; a source electrode and a drain electrode disposed on the respective ohmic contact layers; and an opaque organic light-shielding film disposed on the source electrode, the drain electrode and the amorphous semiconductor film for reducing optical leakage current, the light-shielding film being composed essentially of photoresist material containing black carbon.
Claim 10
Dependent Claim
20 words
A thin film transistor according to claim 7; wherein the light-shielding layer has a thickness of 0.5 to 3 μm.
Claim 11
Dependent Claim
17 words
A thin film transistor according to claim 7; wherein the photoresist material comprises phenol resin and quinone-diazide.
Claim 12
Dependent Claim
18 words
A thin film transistor according to claim 7; wherein the photoresist material comprises a positive type photoresist material.
References Cited (Backward Citations)
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US4764450A
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JPS61145870A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-10 | 1994-03-12 | 1994-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-10 | 1998-03-12 | 1998-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-10 | 2002-03-12 | 2002-09-11 | $7700.00 | Window Closed / Lapsed |