Czochralski (CZ) silicon wafers were firstly subjected to a variety of ramping annealing from low temperatures to 750℃, and then subjected to a prolonged anneal at 750℃ for up to 64 h. It was revealed that the prior ramping anneal from low temperature lead to strong enhancement of oxygen precipitation in the subsequent annealing, and the lower the starting temperature the stronger the enhancement. It is considered that at low temperatures (450—650℃) the diffusion of oxygen was greatly enhanced and therefore the nucleation of oxygen precipitation was facilitated. Moreover, the slow ramping rate could also increase the stability as well as facilitate the growth of the oxygen precipitate nuclei formed at low temperature. A novel internal gettering (IG) process based on ramping anneal from low temperature has been developed, which can reduce the annealing time and therefore the thermal budget. However, the ramping anneal from low temperature is not available for the application of magic denude zone (MDZ) process.