Mechanism of Design of the Precision Recycle Process of a Color Filter Using Electrochemical Etching

Abstract

An effective and low-cost mechanism is presented which uses electrochemical etching and design-tool electrodes as a precision recycle process of indium-tin-oxide (ITO) layer removal from the color filter surface of an optoelectronic flat-panel display instead of chemical etching. Through the ultraprecise removal of thin-film microstructure, the semiconductor optoelectronics industry can effectively recycle defective products, thereby reducing production costs. In the current experiment, the author uses a fifth-generation thin-film transistor liquid-crystal display. A large cathode diameter accompanied by a small gap width between the cathode and the workpiece takes less time for the same amount of ITO layer removal. An adequate color filter feed rate combined with sufficient electric power produces a fast etching effect. A higher electrode rotational speed, a higher temperature, or a higher concentration of the electrolyte corresponds to a higher etching rate for the ITO layer. Pulsed direct current can improve the effect of dreg discharge and is advantageous when combined with fast workpiece feed rate. However, this raises the current rating. In a short amount of time, electrochemical etching can remove the ITO layer easily and cleanly.