掺钼氧化锌透明导电薄膜光学性质研究

Optical Properties of Mo-Doped ZnO Transparent Conductive Films

采用直流磁控反应溅射制备了掺钼氧化锌透明导电薄膜。研究了掺钼氧化锌薄膜的结构、表面形貌及其光学和电学性能。原子力显微镜扫描显示薄膜表面较为平整致密。制备出的掺钼氧化锌薄膜最低电阻率为9.4×10-4Ω.cm,相应载流子迁移率为27.3cm2V-1s-1,载流子浓度为3.1×1020cm-3。在可见光区域的平均透射率大于85%,折射率(550nm)为1.853,消光系数为7.0×10-3。通过调节氧分压可以调节薄膜载流子浓度,禁带宽度随载流子浓度的增加由3.37增大到3.8eV,薄膜的载流子有效质量m*为0.33倍的电子质量。

The Mo-doped ZnO （ZMO） transparent conductive films were grown by DC reactive magnetron sputtering on glass substrates. Its surface microstructures and optical properties of the ZMO films were characterized with atomic force microscopy and conventional optical probes. The impact of the film growth conditions on the film quality was studied. The results show that the compact, smooth film has a minimum resistivity of 9.4 × 10^-4Ω· cm, a carrier mobility of 27.3cm2V^-1s^-1 ,a carrier concentration of 3.1 × 10^-20cm^-3, and an average transmittance of 85% in the visible light range. Besides, the refractive index and extinction coefficient at the wavelength of 550nm are 1.853 and 7.0 × 10^-3, respectively. As the carrier concentration increases, the band gap widens from 3.37 to 3.8eV, and the effective mass of the carrier was found to be 0.33 times of an electron mass.