The behaviors of ox ygen precipitation both in heavily B??doped samples and in heavily Sb?? doped ones are invest ig ated by DXS. The effect of thermal treatment, temperature and dopant types on oxy?gen precipitat ion is analy zed. T he ex perimental result s show that the integrity of the w afers surface is im??proved w hen they are ret reated under high temperature for a long t ime. T his phenomenon is caused by the interact ion of the defect s induced by oxygen precipitat ion, by the redissolut ion of oxygen precipitat ion, and by the external diffusion of the oxygen. T he ox ygen precipitat ion in heavily B??doped samples is more obvious than that in heav ily Sb??doped ones. Moreover, the redissolut ion phenomenon of oxygen precipitation is ob??served, and this just conf irms the analysis on the above ex periment result s.