DEVICE ISOLATION METHOD OF SEMICONDUCTOR

摘要

forming a first oxide film on a semiconductor substrate; forming an oxidation stopper having an open aperture revealing the part where an isolation region is formed on the first oxide film; forming an oxygen ion layer in the substrate by implanting oxygen ion into the front surface of the substrate using the oxidation stopper as a mask; forming a spacer on the side wall of the oxidation stopper; forming a trench by etching the oxygen ion layer using the spacer as an etching mask; thermal-oxidation of the oxygen ion layer by thermal annealing; and forming a second oxide film to fill the trench.