REDUCED PROCESS METHOD FOR THIN-FILM-TRANSISTOR LIQUID-CRYSTAL DISPLAY (TFT-LCD) WITH DRY-ETCHING TAPERED ITO DATA BUS LINES

For years, many studies have been conducted for the purpose of reducin g the number of TFT processes. We have developed a top-gate TFT-LCD fa bricated using only indium-tin-oxide (ITO: In2O3-SnO2) data bus lines by eliminating the metal data bus line process. Substituting ITO dry-e tching for wet-etching allows tapering of the side walls of thick ITO data bus lines. Controlling the tapered angle of ITO data bus lines to be less than 40 degrees results in successful fabrication of a transi stor with no offset voltage. As a result, we have developed a 6-inch-d iagonal TFT-LCD fabricated with data bus lines as well as drain-source electrodes of single-layered ITO.