United States Patent  [in E Patent Number: Re. 33,829
Castleberry  Reissued Date of Patent: Feb. 25, 1992
 REDUNDANT CONDUCTOR STRUCTURES FOR THIN FILM FET DRIVEN LIQUID CRYSTAL DISPLAYS
 Inventor: Donald E. Castleberry, Schenectady, N.Y.
 Assignee: General Electric Company,
 Appl. No.: 487,4*2
 Filed: Mar. 2,1990
Related U.S. Patent Documents
 Patent No.: 4,804,953
Issued: Feb. 14, 1989
Appl. No.: 97,247
Filed: Sep. 16,1987
 Continuation of Ser. No. 756,640, Jul. 19, 1985, abandoned.
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Primary Examiner—Alvin E. Oberley
Assistant Examiner—Richard Hjerpe
Attorney, Agent, or Firm—Marvin Snyder; James C.
Redundancy is provided in the data and gate lines of the liquid crystal display device for improved reliability and greater fabrication yield. The data lines in particular are preferably fabricated in a multilayer structure with two conductive layers sandwiching a narrow insulating strip. The presence of the insulating strip permits the upper conductive line to be formed without step jumps which can exhibit a tendency for poor electrical connection. The upper and lower conductive layers of the data line are in contact for the length of the lower data line, contact being made on either side of the narrower insulating strip. Similar redundancy, without the necessity of providing an intermediary insulating layer is also provided for the gate lines. The redundancy provided in the present invention is particularly suitable for fabrication methods employed in thin film FET driven LCD devices.
56 Claims, 7 Drawing Sheets