Electron spin resonance centers associated with oxygen precipitates in Czochralski silicon crystals

We have previously concluded that the oxygen-precipitate-associated defects that we identified by the deep levels at E-v+0.30 eV and E-c-0.25 eV were the P-b centers generated in the interface between the oxygen precipitates and the surrounding silicon crystal lattice [M. Koizuka and H. Yamada-Kanet a, J. Appl. Phys. 84, 4255 (1998)]. In order to confirm this conclusion, we have made electron spin resonance (ESR) measurements on the Czochralski-gr own silicon crystals containing the oxygen precipitates generated by the tw o-step anneals of 500 degrees C, 20 h+700 degrees C, 60 h. We have found th e ESR lines whose g values well coincide with those of the P-b0 and P-b1 ce nters. Thus it has been clarified that the P-b0 and P-b1 centers are genera ted by the oxygen precipitation as well as by the thermal oxidation. The pr esent successful application of the ESR method to the annealed silicon crys tals suggests that it can be a useful tool to characterize the precipitatio n state of the oxygen in silicon. (C) 2000 American Institute of Physics. [ S0021- 8979(00)06215-0].