METHOD FOR INTRODUCING LATTICE DEFECT FOR GETTERING OF IMPURITY ATOM INTO REAR OF SEMICONDUCTOR WAFER

摘要

PURPOSE:To make the formation of rear side damage possible by a method wherein ice particles are injected at the angle of 30-70 deg. against the rear side of a semiconductor wafer. CONSTITUTION:A container 1 is filled up with the liquid nitrogen 3 fed from a liquid nitrogen source 2. Waves of several millimeters are generated on the surface of the liquid nitrogen 3 by jetting out nitrogen gas from an air diffusing tube 4. Pure water is fed to a nozzle 6 from a pure water source 7 and, at the same time, nitrogen gas is fed. Then, the pure water is jetted out from the nozzle 6. The fog-like pure water injected into the liquid nitrogen 3 as above-mentioned is turned into microscopic ice particles 8 in a moment. The ice particles 8 are injected by a blasting device 11. A rear damage is formed by introducing a lattice defect using the impact generated by colliding the injected ice particles against the rear side of a semiconductor wafer at the angle of 30-70 deg. against the rear side of the wafer. The possibility of attraction of contaminants by static electricity and the like, generated by the impact of injection of ice particles formed by the water for which specific resistance is lowered to 1 MOMEGA/cm or less by allowing the ultra pure water to contain carbonic gas.