Attempts to Apply Thin Film Transistors to Electroluminescent Displays

ABSTRACTThe objectives of the two programs described here were to develop fabrication processes for flat panel displays using an active matrix of thin film transistors (TFT) behind an electroluminescent (EL) display medium. The programs were carried out under ERADCOM contracts DAAB07-76-C-0027 with Westinghouse R&D Center and DAAB-07-77-C-0583 with Aerojet Electrosystems Company. The huge amount of information about the processes and technology generated through the efforts of capable and dedicated people who worked on these programs was, in spite of everything, not enough to achieve the stated objectives. The fabrication processes developed did not result in repeatable, reliable display devices. The solutions applied to one set of problems tended to uncover new problems previously unseen, but this continual problem solving process probably generated more information about the technology than results from many programs in which the goals are achieved. The improved understanding of TFT processes and applicability is the subject of this report.