| 摘要 |
PURPOSE: A method for forming an isolation layer of a semiconductor device is provided to be capable of preventing a gate oxide layer of the upper edge portion of a trench from being thinly formed by forming a polysilicon layer between a semiconductor substrate and the isolation layer. CONSTITUTION: A polysilicon layer(24) is formed on a semiconductor substrate(21), wherein the semiconductor substrate has a trench at the predetermined portion. After depositing an insulating material layer(25a) on the entire surface of the resultant structure for completely filling the trench, an isolation layer is formed by carrying out a polishing process on the resultant structure. Preferably, the polysilicon layer has a thickness of 100-200 angstrom.
|
