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US4956680A Expired / Lapsed US ⏱️ 0.0 years remaining

Thin film transistor

Assignee: LG Display Co Ltd
•
Filing: 1987-12-14
•
Granted: 1990-09-11
•
Expires: 2007-12-14
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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)

US3969751A Cited
US4609930A Cited
US4764450A Cited
JPS61145870A Cited
JPS61244068A Cited
JPS61280659A Cited
US4715930A Cited

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

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