材料期刊网

研究了加热温度与冷却速率对热处理直拉单晶硅少子寿命和间隙铁含量的影响。结果表明,直拉单晶硅在300～1050℃加热40 min,以50℃/s的速率快冷至室温会提高硅片的间隙铁含量,降低硅片的少子寿命;加热温度越高,快冷后硅片的间隙铁含量越高,少子寿命越低;直拉单晶硅片在900～1050℃加热,当以50℃/s的速率快冷至室温,90%以上的铁以沉淀形式存在,其余的铁以间隙态存在。直拉单晶硅片分别经800、900和1000℃加热40 min后在0.017～50℃/s的速率范围冷却,硅片间隙铁含量随冷却速率增加而增加,少子寿命随冷却速率增加而降低,加热温度越高,间隙铁含量上升的幅度越大,而少子寿命下降的幅度越大。

Effects of heating temperature and cooling rate on the minority carrier lifetime and the interstitial iron concentration of Czochralski silicon（Cz-Si） were investigated. The results show that the interstitial iron concentration is higher and the minority carrier lifetime is lower than the original level when the Cz-Si are heated in the range of 300-1050 ℃ for 40 min and cooled to room temperature at a rate as fast as 50 ℃/s, and the interstitial iron concentration increases and the minority carrier lifetime decreases with increase of heating temperature. When the Cz-Si wafers are heated in the range of 900-1000 ℃ for 40 min and cooled to room temperature at a rate as fast as 50 ℃/s, above 90% of the iron in silicon is in the form of iron precipitates while the other is kept as interstitial iron. When the Cz- Si wafers are heated at 800, 900 and 1000 ℃ for 40 min, followed by cooling at different rates, the interstitial iron concentration increases and the minority carrier lifetime decreases with increase of the cooling rate from 0. 017 to 50 ℃/s.