The phenomena of microdefects induced by cavitation for gretting in CZ silicon, are discussed. The microdefects are found to remove unwanted impurities in the active semiconductor devices and are also responsible for plastic deformations of silicon wafer. Transmission Electron Microscopy (TEM) combined with advanced specimen preparation machines is employed to examine the optimum point at which bulk microdefects have beneficial gretting effect in silicon wafer. The silicon wafer immersed in DI water in a cavitation jet and shock waves causing plastic deformations are formed by collapsing of the cavitation bubbles. The dipoles show mixed type dislocations, single line dislocations (S), and a dislocation loop at the region of highest cavitation impact. It is shown that the single cavitation impact caused multiple disintegration of dislocation loops creating single dislocation.