双层预制膜对CIGS薄膜结构和形貌的影响

Influence of Bilayer Precursor Films on Structure and Morphology of CIGS Films

采用中频交流磁控溅射方法,在玻璃基底上依次沉积了Mo、CuIn、CuGa薄膜,制备了CuInGa(CIG)双层预制膜,采用固态硒化法制备获得了Cu(In1-xGax)Se2(CIGS)吸收层薄膜,考察了CuGa层制备过程中工作气压的改变,对CIGS薄膜结构和形貌的影响。采用SEM和EDS观察和分析了薄膜的表面形貌和成分,采用XRD表征了薄膜的组织结构。结果表明,改变溅射制备CuGa层的工作气压,所获得的CIG双层预制膜均由Cu11In9、CuIn和CuGa组成。在溅射制备CuGa层的工作气压为1.0 Pa的条件下所获得的CIG双层预制膜经过硒化后,获得的CIGS薄膜致密。采用不同结构的双层预制膜,在不同的硒化时间下制备的CIGS薄膜,均具有黄铜矿相结构,薄膜具有(112)面的择优取向。

CuInGa（CIG） bilayer precursors were deposited on Mo-coated soda-lime glass substrates by middle frequency a.c. magnetron sputtering of CuIn and CuGa, alternatively. Then, the CIG precursors were selenized in Se vapor to form Cu （ In1-xGax） Se2 （CIGS）. The CIGS films were characterized with X-ray diffraction （XRD）, scanning electron microscopy（SEM） and energy dispersive spectroscopy（EDS）. The results show that argon pressure and selenization time little affect the CIG phase and CIGS stoichiometries. For instance, at different operating Ar pressures, CIG films comprise of Cu11 In19, Culn and CuGa; at an argon pressure of 1.0 Pa, for different selenization time intervals, the phase of CIGS films is chalcopyrite with a （112） preferential growth orientation.