METHOD FOR FORMING GATE STRUCTURE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a gate structure of a semiconductor device is provided to form a gate electrode by forming a mask pattern in which the sidewall of the structure composed of the mask pattern and a floating gate has a good vertical profile. CONSTITUTION: A gate oxide layer is formed on a semiconductor substrate that is separated into a cell region and a peripheral region. A conductive layer is formed on the gate oxide layer. A mask layer is formed on the conductive layer. A part of the mask layer is etched to form the mask pattern with a vertical profile by using oxide layer etching gas and polymer etching gas. A nitride layer and a buffer oxide layer are sequentially stacked to form the mask layer.