METHOD FOR FORMING SHALLOW TRENCH ISOLATION LAYER OF SEMICONDUCTOR DEVICE HAVING IMPROVED GAP-FILLING PROPERTY

摘要

PURPOSE: A method for forming an STI(Shallow Trench Isolation) layer of a semiconductor device is provided to improve gap-filling property by filling sequentially a trench using an SOG(Spin On Glass) layer and an HLD(High-temperature Low-pressure Deposition) oxide layer. CONSTITUTION: A mask pattern is formed on an active region of a substrate(300). A first trench(304) is formed in the substrate by using the mask pattern as a mask. An SOG layer(306a) is gap-filled in the first trench. By baking and curing the SOG layer, a second trench is formed. An HLD oxide layer(310b) is gap-filled in the second trench. The gap-filled HLD oxide layer is annealed. The annealed HLD oxide layer is polished to expose the mask pattern. The exposed mask pattern is removed.