Multi-LOCOS (local oxidation of silicon) isolation process

摘要

A new method of local oxidation using a multiple process is described. A thin silicon oxide layer is formed over the surface of a silicon substrate. A layer of silicon nitride is deposited overlying the silicon oxide layer. The silicon oxide and silicon nitride layers are patterned to provide openings of the smallest size exposing portions of the silicon substrate to he oxidized and growing field oxide regions within these smallest size openings. The patterning and growing of field oxide regions is repeated for each larger size of opening required. The silicon nitride and silicon oxide layers are removed, thereby completing local oxidation of the integrated circuit.