METHOD FOR FABRICATING TRENCH ISOLATION OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating trench isolation of a semiconductor device is provided to maintain a round profile in the upper corner of a trench by forming a shallow thickness of a thermal oxide layer, and to guarantee reliability of a gate oxide layer by preventing the gate oxide layer from being thinly formed in the upper corner of the trench. CONSTITUTION: A predetermined depth of a semiconductor substrate(100) is etched to form a trench. A conformal material layer is formed on the bottom and both sidewalls of the trench. A thermal oxide process is performed to eliminate the etch damage to the semiconductor substrate so that a thermal oxide layer(200) is thinly grown between the conformal material layer and the semiconductor substrate. A nitride layer liner(220) is formed on the conformal material layer. A trench isolation material(240) is formed to completely fill the trench.