METHOD FOR FABRICATING TFT TO PERFORM ETCH PROCESS WITH SMOOTHNESS, UNIFORMITY AND GOOD SELECTIVITY

摘要

PURPOSE: A method for fabricating a TFT(thin film transistor) is provided to perform an etch process with smoothness, uniformity and good selectivity by etching a silicon layer by mixture gas including CHF3 gas and O2 gas or HF gas and O2 gas. CONSTITUTION: A metal layer deposited on a silicon layer is patterned to form a metal interconnection. The silicon layer not covered with the metal interconnection is etched along the end part of the metal interconnection. Between a process for forming the metal interconnection and a process for etching the silicon layer not covered with the metal interconnection along the end part of the metal interconnection, the silicon layer is etched by mixture gas including oxygen gas and gas composed of molecules having at least hydrogen and fluorine elements.