A method of forming a semiconductor device isolation region for forming a shallow trench using a sacrificial oxide film

摘要

First, the silicon substrate of the region in which the device isolation region is to be formed is etched to form a shallow trench of 1 μm or less, and then a sacrificial oxide film is formed on the surface of the etched silicon substrate, and then removed again to round the edges of the trench. A pad oxide film is formed thereon, and a silicon nitride film is deposited on the pad oxide film. Then, the silicon nitride film of the trench portion is removed, and the trench is filled with an oxide film or the like to form a semiconductor device isolation region.