A novel way of preparation of high quality substrate material for highly efficient solar cells

研究了Ge共掺杂对b掺杂CZ-Si晶体少数载流子寿命（MCL）的影响。随着Ge浓度从0增加到1×1020 cm-， MCL从110增加到176μs。3. Ge共掺杂抑制了B掺杂CZ-Si的光致降解（LID）。此外，随着Ge浓度的增加，B/Ge共掺CZ-Si中与生长微缺陷（GMD）相关的流态缺陷（FPD）密度降低。间质氧（Oi）浓度随Ge浓度的升高而降低。在B和Ge共掺CZ-Si中，抑制LID效应与低浓度的B- o相关缺陷产生有关。从钢锭冷却时锗空位缺陷形成的角度，探讨了锗浓度对fpd和Oi浓度降低的影响机理。x=0-0的掺ga Si1-xGex合金单晶。6株用佐克拉尔斯基法成功生长。结果表明，在x=0时，随着Ge含量的增加，MCL增大，FPD密度减小；当超过0时，趋势反转。03. Ge在GMD的形成中起着重要作用。

The effect of Ge codoping on the minority carrier lifetime(MCL) in B-doped Czochralski-silicon(CZ-Si) crystals was investigated. The MCL increased from 110 to 176μs with increasing Ge concentration from 0 to 1×1020 cm-. 3. Light-induced degradation(LID) of B doped CZ-Si was suppressed by Ge codoping. Moreover, the flow pattern defect(FPD) density related to grown-in micro-defects(GMD) in B/Ge codoped CZ-Si decreased with increasing Ge concentrations. The interstitial oxygen(Oi) concentration was decreased as the Ge concentration increased. The suppressed LID effect in the B & Ge codoped CZ-Si was associated with the low concentration of B-O related defect generation. The mechanism by which the Ge concentration influence on the reduction of FPDs and Oi concentration is discussed based on Ge-vacancy defect formation at cooling the ingots. Ga-doped Si1-xGex alloy single crystals with x=0-0. 06 were successfully grown by Czochralski method. The results show that the MCL was increased and FPD density was decreased as the Ge composition increases up to x=0. 03 and the trend reverses when beyond 0. 03. The Ge plays an important role on the GMD formation.