Photofabricated thin-film transistor arrays

Thin-film-transistor (TFT) arrays were fabricated entirely with photolithographic pattern delineation of transistor materials which were deposited sequentially in a multipump-down-mode. Classical metal shadow masks were not used. Results obtained from 1" square arrays containing 25 TFT\´s with a finest line width of 25 µm demonstrate feasibility of complete photolithographic fabrication of TFT microcircuits and drive matrices. Process options, associated advantages and disadvantages for large-area applications and device characteristics, including reproducibility and reliability, are presented.