| 摘要 |
PURPOSE: An isolation method for a semiconductor device is provided to control residual polysilicon everywhere in etching a gate by rounding the profile of the upper portion of a trench when the trench is formed. CONSTITUTION: A silicon substrate(1) is etched to form the trench. An oxide layer is filled in the trench(3) to form a trench-type isolation layer. The trench is formed through a dry etch process using HBr gas. Mixture gas composed of HBr gas and Cl2 gas can be used in the dry etch process.
|
