Gettering of Fe to below 1010 cm−3 in MeV self-implanted Czochralski and float zone silicon

The effects of Si ion fluence and oxygen concentration on secondary defect formation and gettering of metallic impurities in MeV self-implanted silicon have been studied for Czochralski (Cz) and float zone (FZ) silicon by means of deep level transient spectroscopy, secondary ion mass spectroscopy, transmission electron microscopy, and optical microscopy/chemical etching. We found that the density, depth distribution, and number of extended defects is strongly dependent upon both the Si ion fluence and the oxygen concentration. Effective gettering of iron to below 1010 cm−3 can be achieved in both FZ and Cz wafers at implantation doses of 1015 cm−2.