Influence of rapid thermal process on intrinsic gettering in fast neutron irradiated Czochralski silicon
(1.School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China2.School of Science, Tianjin University of Commerce, Tianjin 300134, China3.School of Information and Communication, Tianjin Polytechnic University, Tianjin 300160, China)
Abstract: A rapid thermal process (RTP) was first introduced into the intrinsic gettering (IG) processes of fast neutron irradiated Czochralski (CZ) silicon. The effect of RTP conditions on bulk microdefects (BMDs) and denuded zone (DZ) was investigated. Fourier transform infrared absorption spectrometer (FTIR) was used to measure the concentration of interstitial oxygen ([Oi]). Bulk microdefects were observed by optical microscope. The results show that, according to the variation of [Oi], it is found that RTP doesn’t change the processes of oxygen precipitation in fast neutron irradiated Czochralski silicon. Perfect denuded zone, dense oxygen precipitates and defects form in the bulk of irradiated samples. With increasing temperature of RTP, the width of denuded zone decreases. Increasing RTP cooling rate, the density of Bulk microdefects increases. DZ forms in the sample that annealed in nitrogen atmosphere.
Key words: neutron irradiation; Czochralski silicon; intrinsic gettering; FTIR