METHOD OF FORMING ISOLATION LAYER TO MINIMIZE MOAT USING LINER NITRIDE LAYER

摘要

PURPOSE: A method for forming an isolation layer using a liner nitride layer is provided to minimize moat by restraining the side-etching of the liner nitride layer. CONSTITUTION: A trench is formed in a substrate by using a pad nitride layer(23b) as a mask. A liner nitride layer(26) is formed on the trench. An isolation layer(28a) is formed by filling an insulating layer in the trench and planarizing to expose the pad nitride layer. The pad nitride layer and the liner nitride layer are partially removed by first etching. The isolation layer is partially removed so as to cover the side of the liner nitride layer. The surface of the substrate is exposed by second etching of the pad nitride layer.