Effect of nitrogen doping on denuded zone formed by rapid thermal process in Czochralski silicon wafer

摘要

Denuded zone (DZ) formed by rapid thermal process (RTP) followed with the low-high (Lo-Hi) annealing in nitrogen-doped Czochralski (NCZ) silicon wafer was studied in this paper. In comparison with the conventional CZ silicon, the DZ in NCZ silicon was a little narrower, while the bulk microdefects were much denser, as a result of nitrogen-enhanced oxygen precipitation. It was also found that DZs within CZ and NCZ silicon wafers shrunk notably when further subjected to rigorous oxygen precipitation annealing, however, a width of substantial DZ remained within either wafer. Furthermore, it is definitely proved that the nitrogen doping does not affect the formation of defect-free DZ by the RTP-based internal gettering (IG) process.