Patent US5432122A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5432122A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making a thin film transistor by overlapping annealing using lasers

Assignee: LG Electronics Inc
•
Filing: 1993-11-03
•
Granted: 1995-07-11
•
Expires: 2013-11-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The present invention provides a method of making a thin film transistor for driving a liquid crystal display comprising the steps of forming a gate electrode on a glass substrate and forming an insulating layer and an amorphous silicon layer in turn on said glass substrate and said gate electrode, and scanning laser beams on the surface of said amorphous silicon layer with the end portions of the respective scanned laser beams being overlapped. According to the method of making a thin film transistor for driving a liquid crystal display of the present invention, a thin film transistor suitable for HDTV, the field effect mobility of which is high, is achieved. Further, in making a thin film transistor, a separate processing step is not required and the number of processing steps can be reduced because constructional features of a TFT are utilized.

Inventors

  • 👤 Kie S. Chae

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 07:09
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6745; H10P; H10P14/00; H10P14/20; H10P14/38; H10P14/3802; H10P14/3808; H10P14/3816; H10D30/6729; H10D30/673; H10D30/6733; H10D86/00; H10D86/01; H10D86/021; H10D86/0221; H10D86/0223; H10D86/0227; H10P14/29; H10P14/2901; H10P14/2922; H10P14/32; H10P14/3202; H10P14/3238; H10P14/3241; H10P14/3242; H10P14/3244; H10P14/3248; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/381; H10P14/3814; H10P14/382

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 143 words
A method of making a thin film transistor for driving a liquid crystal display comprising the steps of: forming a gate electrode on a glass substrate and forming an insulating layer and an amorphous silicon layer in turn on said glass substrate and said gate electrode; scanning laser beams on the surface of said amorphous silicon layer with the end portions of the respective scanned laser beams being overlapped; and scanning said laser beams through an optical system including prisms arranged at intervals so that the overlapped portions of the laser beams pass through the prisms for increasing the density of the laser beams scanned on overlapped portions compensating for a difference in optical efficiency between portions of the transistor scanned by the overlapped part of the laser beam and portions of the transistor scanned by a non-overlapped part of the laser beam.
Claim 2
Independent Claim 143 words
A method of making a thin film transistor for driving a liquid crystal display comprising the steps of: forming a gate electrode on a glass substrate and forming an insulating layer and an amorphous silicon layer in turn on said glass substrate and said gate electrode; scanning laser beams on the surface of said amorphous silicon layer with the end portions of the respective scanned laser beams being overlapped; and scanning said laser beams through an optical system including prisms arranged at intervals so that the overlapped portions of the laser beams pass through the prisms for increasing the density of the laser beams scanned on overlapped portions compensating for a difference in optical efficiency between portions of the transistor scanned by the overlapped part of the laser beam and portions of the transistor scanned by a non-overlapped part of the laser beam.
Claim 3
Dependent Claim 27 words
A method of making thin film transistor for driving liquid crystal display as claimed in claim 1, wherein said laser beam is scanned through a cylindrical lens.
Claim 4
Dependent Claim 39 words
A method of making thin film transistor for driving a liquid crystal display as claimed in claim 1, further comprising a step of applying a protective layer on said amorphous silicon layer prior to scanning of said laser beam.
Claim 5
Dependent Claim 29 words
A method of making thin film transistor for driving liquid crystal display as claimed in claim 1, wherein the construction of said thin film transistor is dual gate construction.
Claim 6
Independent Claim 79 words
A method of making a thin film transistor for driving a liquid crystal display comprising the steps of: forming a gate electrode on a glass substrate and forming an insulating layer and an amorphous silicon layer in turn on said glass substrate and said gate electrode; applying a protective layer on said amorphous silicon layer; and scanning laser beams on the surface of said amorphous silicon layer with the end portions of the respective scanned laser beams being overlapped.
Claim 7
Independent Claim 79 words
A method of making a thin film transistor for driving a liquid crystal display comprising the steps of: forming a gate electrode on a glass substrate and forming an insulating layer and an amorphous silicon layer in turn on said glass substrate and said gate electrode; applying a protective layer on said amorphous silicon layer; and scanning laser beams on the surface of said amorphous silicon layer with the end portions of the respective scanned laser beams being overlapped.

References Cited (Backward Citations)

US4309225A Cited
US4439245A Cited
JPS6346776A Cited
JPH0233935A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-07-10 1999-01-09 1999-07-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-07-10 2003-01-09 2003-07-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-07-10 2007-01-09 2007-07-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag