Method of making integrated transistor matrix for flat panel liquid

Abstract

Substantial advantages over existing integrated transistorized matrices for driving flat panel liquid crystal displays may be achieved by the use of silicon on sapphire (SOS) and related technologies. Among the advantages are good isolation to prevent cross talk between circuit elements, simplified processing, reduced pinhole sensitivity, the possibility of utilizing the display in a back-lighted, transmissive mode of operation, and a greatly reduced sensitivity to ambient light. In the preferred embodiment disclosed, an integrated storage capacitor is associated with each transistor in the array. One plate of this capacitor, as well as the transistor and a plurality of vertical drain buses for the carrying of video signals may all be formed in a single processing step. In another single processing step it is possible to form the second plates of the capacitors, the gate electrodes and a plurality of horizontal gate buses upon which control signals may be impressed for line at a time addressing. Also in the preferred embodiment each bottom capacitor plate of a given vertical array is electrically shorted one to another thereby reducing the number of external ground connections required.