Study of internal versus external gettering of iron during slow cooling processes for silicon solar cell fabrication
نویسندگان
چکیده
The effect of slow cooling after different high temperature treatments on the interstitial iron concentration and on the electron lifetime of p-type mc-Si wafers has been investigated. The respective impacts of internal relaxation gettering and external segregation gettering of metal impurities during an extended phosphorous diffusion gettering are studied. It is shown that the enhanced reduction of interstitial Fe during extended P-gettering is due to an enhanced segregation gettering while faster impurities like Cu and Ni are possibly reduced due to an internal gettering effect.
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