GAS ETCHANT COMPOSITION AND ETCHING METHOD FOR SIMULTANEOUSLY ETCHING SILICON OXIDE AND POLYSILICON IN SEMICONDUCTOR PROCESS AND METHOD FOR MANUFACTURING SEMICONDUCTOR MEMORY DEVICE USING THE SAME

摘要

And polysilicon dry etching gas composition of the polysilicon and silicon oxide is etched back to the same speed of the silicon oxide effectively at the same time substantially, discloses an etching method, and a method for manufacturing a capacitor using the same using the same. The dry etching gas is carbon tetrafluoride and nitrogen gas is 25 to 40: is composed of a mixed gas mixed in the first, the ratio of the etch rate of the poly etch rate and the oxide of silicon is 0.8 to 1.2: 1. To be able to be removed by etching the polysilicon and the oxide layer on the same etching equipment, and the poly to remove the composite layer of silicon oxide and effectively, it is possible to obtain a good upper surface profile. Polysilicon particles in the subsequent steps can be prevented that the polysilicon bridge formed out away.