中文摘要：

采用H2,He混合气体稀释等离子辅助反应热化学气相沉积法生长微晶硅锗薄膜,并在生长过程中对等离子体进行光发射光谱在线监测.结果表明：混合气体稀释法可以有效提高等离子体中的原子氢数目,降低等离子体中的电子温度;用XRD和光暗电导率表征样品的微结构和光电特性时发现,通过优化混合稀释气体中He和H2气体的比例,能够减少薄膜中的缺陷态,促进薄膜〈220〉择优取向生长,有效改善微晶硅锗薄膜结构,提高光电吸收性能.

英文摘要：

H2 and He gas mixture diluted very high frequency plasma assisted reactive thermal chemical vapor deposition （VHFPA- RTCVD） is used to prepare μc-SiGe： H thin films, and the optical emission spectrum is used to in situ monitor the reacting plasma during the growing process. It is observed that H2 and He gas mixture dilution is effective in increasing the number of Hα^＊ and reducing the temperature of electrons in the plasma. X-ray diffraction （XRD） and photo- and dark-conductivity measurement show that by optimizing the fractions of H2 and He in the mixture the defect states are reduced, which prompted the growth of 〈 220 〉 and improved the structure, and the optical-electronical properties of the film are enhanced.