SEMICONDUCTOR DEVICE OF TRENCH ISOLATION TYPE AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A method for manufacturing a semiconductor device of a trench isolation type is provided to prevent a dent phenomenon by performing a full back process while performing a trench isolation process, and to improve stability and reliability by making the corner portion of a substrate have a smoothly-curved shape and by preventing a gate oxide layer from being thinly formed on the corner portion of the substrate. CONSTITUTION: An etch protection layer pattern is formed on the substrate(30) to define an active region. The substrate is etched to form a trench by using the etch protection layer pattern as an etch mask. A thermal oxide layer is formed on the sidewall of the trench. The trench having the thermal oxide layer is filled with a chemical vapor deposition(CVD) silicon oxide layer to form an isolation layer(41'). The etch protection layer pattern is eliminated from the substrate having the isolation layer. The thermal oxide layer is eliminated from the upper sidewall of the trench by a thickness of 100-350 angstrom on a basis of the upper surface of the substrate. The gate oxide layer is formed on the active region and the substrate exposed to the upper sidewall of the trench.