Dot-matrix liquid crystal display

• US 4,740,782 A
• Filed: 09/03/1986
• Issued: 04/26/1988
• Est. Priority Date: 07/12/1982
• Status: Expired due to Term

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Hosiden Electronics Co. Ltd. (Hosiden Corporation)
• Inventors: Ukai, Yasuhiro, Aoki, Shigeo, Tamamura, Junichi
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US06/903,332
• Time in Patent Office: 601 Days
• Field of Search: 340/718, 340/719, 340/784, 340/701, 350/334, 350/343, 29/571
• US Class Current: 345/92
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: Y10S 438/949 Energy beam treating radiation resist on semiconductor

Abstract

A liquid crystal cell comprises a liquid crystal sealed between a pair of confronting transparent substrates. A multiplicity of semiconductor driver elements are substantially uniformly distributed over an inner surface of one of the substrates. The semiconductor driver elements have output electrodes connected respectively to matrix element electrodes formed on the inner surface of said one of the substrates. A driver circuit is formed as a semiconductor integrated circuit on an extension of the inner surface of said one of the substrates for selectively driving the semiconductor driver elements.

The driver circuit comprises a plurality of thin-film transistors each of which includes a semiconductor layer which has enhanced carrier mobility achieved through annealing.

Claims

1. A dot-matrix liquid crystal display comprising:

a first transparent substrate fabricated of an insulating material;

a second transparent substrate fabricated of an insulating material disposed closely adjacent and parallel to said first substrate and having marginal edges sealed to said first substrate to form a cell;

a liquid crystal sealed in said cell;

a common electrode deposited substantially entirely on an inner surface of said second substrate to define a display area of said liquid crystal display;

a plurality of transparent matrix element electrodes formed in rows and columns directly on said first substrate to define display elements of a dot-matrix within said display area;

a plurality of transparent row electrode lines formed in rows directly on said first substrate to extend along the respective rows of said matrix element electrodes;

element drive thin-film transistors arranged in rows and columns on said first substrate within said display area, each of said thin-film transistors having a transparent source electrode formed directly on said first substrate integrally with a corresponding one of said row electrode lines, a transparent drain electrode formed directly on said first substrate integrally with a corresponding one of said matrix element electrodes, said source and drain electrodes being closely adjacent to one another, an amorphous silicon semiconductor layer formed on said first substrate to extend between and overlap said closely adjacent source and drain electrodes, a gate insulation film formed to cover said semiconductor layer, and a gate electrode formed on said gate insulation film in spaced facing relation to said semiconductor layer, said gate insulation film substantially entirely covering said display area;

column electrode lines formed integrally with the corresponding columns of said gate electrodes on said gate insulation film in a direction perpendicular to said row electrode lines;

said first substrate being larger than said second substrate to define a marginal substrate portion; and

driver circuit means on said marginal substrate portion, said driver circuit means comprising a semiconductor integrated circuit for selectively activating said element drive thin-film transistors and being connected to respective ones of said element drive thin-film transistors via connection lines formed integrally with said row and column electrode lines, said driver circuit means comprising a column drive integrated circuit and a row drive integrated circuit for activating the said element drive thin-film transistors which are located at the points where selected columns and rows cross one another, said row and column drive integrated circuits comprising thin-film transistors having the same structure as said element drive thin-film transistors and being formed simultaneously therewith, the said semiconductor layer of each of the thin-film transistors in said driver circuit means having enhanced carrier mobility achieved through annealing.