METHOD FOR FORMING ISOLATION LAYER OF SEMICONDUCTOR DEVICE TO PREVENT MOAT BY SURROUNDING THE ISOLATION LAYER USING OXIDE PATTERN

摘要

PURPOSE: A method for forming an isolation layer of a semiconductor device is provided to prevent moat at a trench top corner in cleaning by surrounding the isolation layer using an oxide pattern. CONSTITUTION: A trench(34) is formed by etching a field region of a substrate(31) using a pad oxide pattern(32) and a pad nitride pattern. A first oxide layer is filled in the trench. The pad nitride pattern is removed. A second oxide layer is deposited on the resultant structure. An oxide pattern(36a) is formed to surround the first oxide layer filled in the trench by selectively etching the second oxide layer. By cleaning the resultant structure, the oxide pattern and the pad oxide pattern are removed, thereby forming an isolation layer(35a).