Structure and method to preserve STI during etching

摘要

Disclosed is a method of protecting a semiconductor shallow trench isolation (STI) oxide from etching, the method comprising lowering, if necessary, the upper surface of said STI oxide to a level below that of adjacent silicon active areas, depositing a nitride liner upon said STI oxide and adjacent silicon active areas in a manner effective in defining a depression above said STI oxide, filling said depression with a protective film, and removing said nitride layer from said adjacent active areas.