WAFER ABRASIVES AND MANUFACTURE OF SEMICONDUCTOR DEVICE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To prevent generation of plug loss and microscratch, by properly setting the average grain diameter of silica and the amount of NH4 OH. SOLUTION: Silica whose average primary grain diameter is 40-110nm, NB4 OH of 0.01-0.03mol/l and organic oxidizing agent are contained in wafer abrasives for chemically and mechanically polishing a tungsten film, a tungsten plug free from plug loss is formed, and generation of microscratch can be prevented. When the amount of NH4 OH exceeds 0.03mol/l, the wet-etching rate becomes high, and a large plug loss is formed. When the amount of NH4 OH is at most 0.01mol/l, the abrasive rate becomes too low. A practical abrasive rate can be ensured in the condition that the average primary grain diameter of silica is 40nm. When the average primary grain diameter of silica exceeds 110nm, microscratch is generated on the surface of an oxide film.