Cao Yu, Zhang Jian-Jun, Li Tian-Wei, Huang Zhen-Hua, Ma Jun, Ni Jian, Geng Xin-Hua, Zhao Ying. Optimization of the longitudinal structure of intrinsic layer in microcrystalline silicon germanium solar cellJ. Acta Physica Sinica, 2013, 62(3): 036102. DOI: 10.7498/aps.62.036102