p型宽带隙半导体CuAl_(1-x)Fe_xO_2的光电性能研究

Research on Optical and Conductivity Properties of p-type Conducting CuAl_(1-x)Fe_xO_2 with Wide Band Gap

采用固相反应合成了CuAl1-xFexO2单相多晶材料,系统报道了该系列样品的X射线衍射(XRD)、紫外吸收光谱以及电学性能的测量。结果表明,Fe3+取代CuAlO2中的Al3+,不改变材料的晶体结构,随着掺杂量的增加,材料的光学带隙宽度逐渐减小,导电性能明显提高。当x=0.10时,样品的室温电导率达到3.38×10-1S·cm-1;所有掺杂样品的电导率随温度变化曲线在近室温区,很好地符合Arrhenius关系,其热激活能为20～32meV;Hall系数均为正值,表明所有样品都为p型半导体。

A series of Fe doped CuAl1-xFexO2 powder samples were successfully synthesized by solid state reaction, and their electrical and optical properties were investigated. The results show that the conductivity has a notable improvement after Fe^3＋ doped and the structure has not changed, and the optical band gaps of CuAl1-xFexO2 decrease with Fe^3＋ doped. When x=0.10, the highest conductivity reaches 3.38× 10^-1 S·cm^-1, and reciprocal temperature dependence of electrical conductivity agrees well with the Arrhenius relationship in the range of 160-300 K for the samples of x-=0, 0.05, 0.10 and 0.20. It indicates that the electrical conductivity is ascribed to thermal activation. p-type conduction was confirmed by the positive Hall coefficient.