TRENCH OF SEMICONDUCTOR DEVICE AND METHOD FOR FORMING TRENCH

摘要

PURPOSE: A trench of a semiconductor device is provided to prevent the edge of a sidewall of a trench from being dug in a wet-etch process by leaving a predetermined thickness of a trench oxide layer on a trench in a CMP(chemical mechanical polishing) process after the trench oxide layer is formed and by dry-etching a sidewall oxide layer while using a photoresist layer pattern with a little greater width than the trench so that the sidewall oxide layer is left on the sidewall of the trench. CONSTITUTION: The trench(100) is formed as an isolation region in a semiconductor substrate(11) and is filled with an insulation material. The trench protrudes from the semiconductor substrate by a predetermined height. A hetero layer of a predetermined width is formed on the outer surface of the sidewall of the trench and on the semiconductor substrate, composed of a different material from the insulation material buried in the trench. The insulation material of a predetermined thickness is formed on the hetero layer.