METHOD FOR FORMING ISOLATION LAYER OF SEMICONDUCTOR DEVICE TO MINIMIZE MOAT

摘要

PURPOSE: A method for forming an isolation layer of a semiconductor device is provided to minimize moat and to prevent field crowding by implanting nitrogen ions into a top rounding portion in STI(Shallow Trench Isolation). CONSTITUTION: A pad pattern including a pad oxide layer and a pad nitride layer is formed on a substrate(21). A trench(29) is formed by patterning the pad pattern and the substrate using an STI mask. A sacrificial oxide layer is formed on the trench, and then nitrogen ions are implanted into the top corner of the trench. A sidewall oxide layer(35) and a linear nitride layer(37) are sequentially formed on the trench. An isolation layer(39a) is then formed by filling a gap-fill oxide layer and planarizing.