A study of roll-printing technology for TFT-LCD fabrication

Recently, potential breakthrough technologies for low-cost processing of TFT-LCDs and new process developments for flexible-display fabrication have been widely studied. A roll-printing process using etch-resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliche plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin-film-transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15-in.-XGA TFT-LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used.