Studies On Growth Of ZnO Thin Films Grown On Si And CIGS Substrates By PECVD And CIGS Solar Energy Cell

ZnO is a direct wide band gap semiconductor with WZ crystal structure. Due to the low growth temperature and high exciton binding energy (60meV) at room temperature, it is an ideal semiconductor material. ZnO with high quality couldn't be obtained due to the limit of semiconductor growth technology at beginning, there was no progress in ZnO application in the field of emiting light research. As the development of semiconductor growth technology, high quality ZnO can be obtained. The researches and developments of ZnO films have attracted great attention and interest from researchers and the industry, because they have realized that ZnO films have many potential applications such as surface acoustic wave devices, planar optical waveguides, transparent electrodes, ultraviolet photodetectors, piezoelectric devices, varistors, gas sensors, UV/violet/blue-LEDs, etc.. And they can be integrated with some materials readily.In this paper, it is firstly reported that ZnO thin films have been deposited on Si(111) substate by self-designed plasma enhanced chemical vapor deposition(PECVD), using carbon dioxide / hydrogen gas and diethylzinc carried by nitrogen gas as reactant sources. The results show that the sheet resistivty and hall mobility of ZnO thin films is 5.4×10⁹ohm/sq, s seperatly. So we apply this technology to fabraticate ZnO thin films on CIGS substrate and ZnS/CIGS substrate, and the first CIGS solar energy cell in China ( n-ZnO /i-ZnO /CIGS/Mo/Glass) without CdS or ZnS buffer has been obtained in the Nankai University. The conversion efficiency is 4 %. Some encouraging results are following as:1. It is firstly reported that high quality ZnO thin films on Si(l 11) substrate have been obtained by self-designed PECVD system, using carbon dioxide / hydrogen gas as oxygen sources. The relation of substrate temperature and ratio of H₂ / CO₂ have been investigated in details. Crystallographic properties and surface morphology of the films are characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The results show that (002) preferred orientation of thin films is obtained and the FWHM value of (002) ZnO thin films...