Removal of bromine containing polymer from plasma etched semiconductor wafer

摘要

A wafer is by spraying water onto the rotating wafer and supplying hydrogen fluoride for part of the spraying time. Polymers containing bromine, chlorine, silicon and carbon are eliminated from a semiconductor wafer, which is partially covered with photosensitive resin, by rotating the wafer at 500-2000 RPM in a nitrogen filled chamber, spraying water onto the centre of the wafer and introducing hydrofluoric acid for a predetermined cleaning period during the spraying operation. Preferred Features: The wafer has a silicon oxide layer bearing polysilicon patterns which are covered with the photosensitive resin and which have vertical walls covered with polymer resulting from plasma etching. The hydrofluoric acid is introduced at 20-90 cm<3>/minute for 3-5 seconds into the chamber at close to atmospheric pressure. The water is deionised water supplied at 430 cm<3>/minute. The chamber is held at 30 deg C.