掺杂对FeS_2薄膜光电性能的影响

EFFECTS OF DOPING IMPURITES IN PYRITE FILMS ON THE OPTICAL AND ELECTRICAL PROPERTIES

采用磁控溅射淀积合金膜和纯铁膜,通过离子注入掺杂,研究了不同条件下FeS2薄膜的晶体结构,光吸收系数、电阻率、载流子浓度等光电性能,并用正电子湮灭谱研究了膜内的空位缺陷。结果表明,掺杂提高了薄膜的导电性能。离子注入使薄膜光吸收系数增加,禁带宽度上升,霍尔迁移率提高;合金溅射导致光吸收系数降低,禁带宽度下降,载流子浓度升高。注入Zn2+退火前空位浓度较大,退火后空位浓度低于纯FeS2膜。

Co-incorporated and Zn-incorporated polycrystalline pyrite films were prepared by thermally sulfurizing alloy and implanting high energy ions into pure FeS2 films. Optical absorption coefficient, absorption edge, electric resistivity, carrier concentrations and Hall mobility of the films were measured and positron annihilation spectroscopy （PAS） was conducted to study microstructure defects in Zn-doped films. Two kinds of doping impurity lead to better conductivity than pure FeS2. Higher optical absorption coefficient, absorption edge and Hall mobility were measured in ions-implanting films, however, alloy films have worse optical absorption coefficient and absorption edge, but higher carrier concendations. PAS have shown more vacancy defects in Zn-doped films before annealing and less vacancy defects after annealing.