本實驗主要是研究Cz晶片內氧凝聚的現象.實驗中,我們採用450℃ - 1000℃二階段與1200℃ - 450℃- 1000℃三階段式熱處理,研究晶片經過 不同熱處理後,氧凝聚的情形.氧凝聚的速率由FTIR量測間隙氧含量決定. 本研究發現,450℃ - 1000℃二階段熱處理的晶片,在450℃熱處理16 - 64小時出現氧凝聚遲滯現象,第二時段的遲滯現象出現在450℃熱處理512 小時以上的晶片裡.經過前置高溫熱處理的晶片也有類似的遲滯現象出現. 同時,我們也發現前置熱處理會加速其後較低溫熱處理時的氧凝聚速率.本 研究裡,我們報告晶片裡的氧凝聚物與微觀結構的觀察,同時也展示FTIR的 吸收光譜圖. In this study, we report a new set of experimentalresults on oxygen precipitation carried out usingCzochralski silicon wafers : a low-high two stepheat-treatment in N2 ambient was employed : thefirst step heat-treatment low temperature ( at 450℃ for 0 - 1024 hours ) is for SiO2 precipitatenucleation and the high temperature step ( at 1000℃ for 0 - 40 hours ) is for precipitate growth. Theoxygen precipitation rate is monitored by measuring the interstitial oxygen concentration in the siliconwafer. Two precipitation retardation phenomena wereobserved on wafers that received prolonged nucleationheart- treatment. First retardation peak whick is morepronounced occurred on the wafers which received l6h - 64 h at 450 ℃ with the microdefect features observed in this study , we believed that thisretardation phenomenon reported by Tan and Kung on 750 ℃ - 1050 ℃ two-step heat-treatment testSecond retardation peak occurred on the wafersheat-treated at 450 ℃for 512 h or longer. Thisretardation peak is relatively weak. And we still notquiet understand the mechanism of this retardationphenomenon. A set of idential wafers were preheated at 1200 ℃ / 1 h in dry N2, prior to the two-step heat-treatment described above. The short hightemperature pre-heat-treated wafers enhanced theoxygen precipitation rate and also revealed thesimiliar retardation phenomena described above, wereport the microdefect features and FT/IR spectra onthe final stage of two-step heat-treatments. Aprofound model is still needed to cover all thephenomena observed.