Method of fabricating shallow trench isolation structure

摘要

A method of fabricating a shallow trench isolation structure is described. A preserve layer is formed on a substrate. A trench is formed in the substrate and the preserve layer. An oxide layer is formed over the substrate to fill the trench. A wet densification step is performed in a moist environment. A planarization step is performed until the preserve layer is exposed. A shallow trench isolation structure is formed.