METHOD FOR FORMING GATE ELECTRODE IN SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a gate electrode in a semiconductor device is provided to be capable of reducing leakage current due to the electric field focused to edge portions of the gate electrode and restraining etch residues. CONSTITUTION: After forming a sacrificial oxide layer(21) on a semiconductor substrate(20), a groove is formed by selectively etching the sacrificial oxide layer(21). After cleaning the groove, a gate oxide layer(23) is formed on the exposed substrate. The first polysilicon layer(24) and a metal film(25) are sequentially formed on the resultant structure including the groove. After partially etching the metal film(25), the second polysilicon layer(26) is formed on the etched metal film(25). After polishing the second and first polysilicon layer to expose the sacrificial oxide layer(21), a gate electrode(27) is formed by selectively etching the exposed sacrificial oxide layer(21).