METHOD FOR MANUFACTURING TRENCH-TYPE ISOLATION LAYER OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a trench-type isolation layer of a semiconductor device is provided to form an isolation layer of which stress is small and out-diffusion of boron is minimized, by forming a silicon oxynitride layer and an oxide barrier layer. CONSTITUTION: A trench is formed in a field region of a semiconductor substrate(10). After a thermal oxide layer(22) is grown on an inner wall of the trench, a silicon oxynitride layer(20) is formed on an interface between the thermal oxide layer and a silicon layer through an annealing process and in a nitrogen oxide atmosphere. A silicon nitride layer(14) is deposited on the entire surface of the inner wall of the trench to form an oxide barrier layer(24). An oxide layer is filled in the trench and planarized to form an isolation layer.