METHOD FOR ETCHING NITRIDE LAYER OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for etching a nitride layer of a semiconductor device is provided to enhance a reliability of an etch process by presenting an optimum etch condition to maximize etch uniformity or minimize a CDB(Critical Dimension Bias) for representing an etch error rate. CONSTITUTION: A method for etching a nitride layer of a semiconductor device comprises the following steps. A mixed gas of CHF3/CF4/Ar is used as a dry etch gas when performing an etch process for a nitride layer formed on a semiconductor substrate. In the mixed gas, a mixing rate of the CHF3 and the CF4 is 1 to 1 and its variable rate is less than ±10.