METHOD FOR FORMING CONTACT HOLE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a contact hole of a semiconductor device is provided to restrain the surface decrease of the bottom of the contact hole by using a polysilicon layer having a negative slope as an etching mask. CONSTITUTION: An oxide layer(203) and a polysilicon layer(205) are sequentially formed on a semiconductor substrate(201). A photoresist pattern(207) is formed on the polysilicon layer for defining a contact forming region. The polysilicon layer is etched for obtaining the etch profile of negative slope by controlling pressure and the gas flow of O2 using the photoresist pattern as an etching mask. The oxide layer is etched by using the photoresist pattern and the polysilicon layer as an etching mask.