METHOD FOR FABRICATING ISOLATION LAYER IN SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a device isolation layer of a semiconductor device is provided to generate a defect of a single layer by reducing the difference between the stress applied around a first trench and the stress applied around a second trench. CONSTITUTION: A first trench(23A) is formed on a substrate(21) by selectively etching the substrate and a second trench(24) with a greater width than that of a first trench is formed. A sacrificial layer(25) is formed on the bottom of a second trench and the upper side of the substrate. The bottom of the first trench is etched using a sacrificial layer as an etching barrier. The sacrificial layer is removed. The insulation material is buried in the first and second trenches.