退火对冶金法太阳能级多晶硅中缺陷影响的研究  

IMPACT OF THERMAL ANNEALING ON THE DEFECTS OF SOLAR GRADE POLYSILICON PRODUCED BY METALLURGICAL METHOD

作　　者：吴洪军[1,2] 陈秀华[1] 马文会[3,2] 蒋咏[3] 梅向阳[3] 张聪[3] 吴兴惠[1] 

机构地区：[1]云南大学物理科学与技术学院,昆明650091 [2]浙江大学硅材料国家重点实验室,杭州310027 [3]昆明理工大学真空冶金国家工程实验室,昆明650093

出　　处：《太阳能学报》2012年第8期1357-1365,共9页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金委员会-云南省人民政府联合基金(U1137601);教育部科学技术研究重点项目(212159);浙江大学硅材料国家重点实验室开放基金(SKL2009-8)

摘　　要：研究了不同条件下退火对冶金法太阳能级多晶硅锭不同部位的位错、晶界及择优生长取向的影响。利用金相显微镜,电子背散射衍射和X射线衍射仪分别对退火前后多晶硅锭的位错、晶界和择优生长取向的变化规律进行表征,结果表明:退火前后多晶硅中的位错密度大小始终是中部<底部<顶部。1100℃下随着保温时间的延长,多晶硅中的位错密度逐渐减小,到5.0h后达到回复的极限程度;小角度晶界比例不断减小,直至消失;大角度晶界中R型晶界比例先增加后减小,CSL晶界比例缓慢增加,孪晶晶界Σ3比例呈稳定地增加,到退火5.0h后,其比例约占30%;主峰〈111〉织构峰强一直增加,〈311〉织构峰强则是逐渐减小至零,而〈511〉、〈531〉、〈620〉织构强度则是先减小、后增大、最后再减小,退火保温5.0h后择优生长取向达到高度一致。另外,还得到了不同温度下的极限回复程度。Impact of thermal annealing on the solar grade polysilicon producect by metallurgical gated under different experiment condition. The dislocation, grain boundaries and preferred growth orientation were characterized by optical microscopy, EBSD and XRD. The results show that the number of dislocation in the polysilicon ingot before or after annealing is always middle 〈 bottom 〈 top. Under 1100℃ condition, the dislocation density is decreased by prolonging the annealing time. It goes to the limit level of returning after 5. Oh. The amount of angle grain boundaries is decreasing steadily, until disappearing; the proportion of R grain boundaries is increasing firstly and then declining; but the proportion of CSL and ∑3 grain boundary increasing steadily, the 3 is about 30% after 5. Oh annealing. The peak intensity of （111 ）always increases, but the （311 〉 reduces gradually to zero. In addition, for（511 ）, （531〉, （620）, firstly, the peak intensities decline, then increase, finally, they decline again. All the crystal grains of different position achieve a high consistent preferred growth orientation after 5. Oh thermal annealing. Moreover, the limit returning level of different temperature conditions is obtained.

关 键 词：多晶硅 退火 位错密度 晶界 

分 类 号：TN304.1[电子电信—物理电子学]