采用不同粒径分布的单晶籽晶进行高效多晶硅铸锭,结果表明单晶籽晶的粒径分布对引晶效果影响显著。籽晶粒径在1~4mm范围时,引晶效果最佳;粒径大于4mm时,硅熔体流延现象的存在导致长晶初期晶体中位错密度偏高,少子寿命降低;粒径小于1mm时,细小的形核点也会影响晶体中的位错密度和少子寿命。对应电池片效率的结果也验证了该结论。
In order to investigate the influence of particle size distribution of the seeds on the crystal growth of high-performance(HP)mc-Si,single crystal seeds with different particle size distribution of were used for casting ingot.The results revealed that the influence of particle size distribution of single crystal seeds on seeding effect was significant.When the particle size of seeds was 1-4mm range,seeding effect was the best.When the particle size of seeds was larger than 4mm,dislocation density was increased and minority carrier lifetime was reduced because of the phenomenon of flow-casting at the beginning of crystal growth.When the particle size of seeds was lower than 1mm,the too small nucleation sites also affected the dislocation density and minority carrier lifetime.Above conclusions also were validated by the results of solar cell efficiency.