METHOD FOR ISOLATING TRENCH DEVICE

摘要

PURPOSE: A method for isolating a trench device is provided to prevent a groove from being generated. CONSTITUTION: A method for isolating a trench device includes a first through ninth step. The first step is to form a first insulating layer(120) on a semiconductor substrate(100). The second step is to form a mask pattern(130) exposing an area for forming a trench on the first insulating layer. The third step is to etch the first insulating layer by using the mask pattern. The fourth step is to reflow the mask pattern in order to flow the mask pattern onto the side wall of the first insulating layer. The fifth step is to form the trench by etching the semiconductor substrate with a predetermined depth by using the reflowed mask pattern(132). The sixth step is to delete the reflowed mask pattern. The seventh step is to fill up the trench by depositing the second insulating layer on the substrate. The eighth step is to delete the second insulating layer deposited on the first insulating layer by using the first insulating layer as a passivation layer. The ninth step is to delete the first insulation layer.