METHOD OF FORMING ISOLATION LAYER OF SEMICONDUCTOR DEVICE USING THERMAL-OXIDATION LAYER

摘要

PURPOSE: A method of forming an isolation layer of a semiconductor device is provided to prevent the edge moat by forming a thermal-oxidation layer at an edge of the isolation layer. CONSTITUTION: A buffer oxide layer(201) and a nitride layer(202) are sequentially deposited on a silicon substrate(200). The substrate is selectively opened by patterning the nitride layer. A spacer material is deposited thereon. A spacer(203') is formed at both sides of the opened portion. A wet-etching process is performed on the resultant structure. A thermal-oxidation layer(204) is formed at the etched portion. A trench is formed by etching the thermal-oxidation layer and the substrate. An isolation layer is filled in the trench.