Preparation And Application Of GZO Transparent Conductive Thin Films

In this paper, we investigated the influence of deposition pressure, sputtering power, high temperature annealing and H-plasma treatment on the properties of Ga-doped ZnO (GZO) films prepared by radio frequency magnetron sputtering (RFMS). Furthermore, we designed a novel crystalline silicon solar cell structure with GZO used as the transparent window and electrode. Preliminary test and study have been carried out. And the main work includes:1. GZO transparent conductive films were deposited on glass substrates by RFMS. The influence of deposition pressure and sputtering power on the structural, morphological, electrical, and optical properties of GZO films were investigated in detail. Films deposited at300℃,0.2Pa and180W exhibit the best photoelectric properties. In addition, the stability of GZO films under high temperature was studied. The films were annealed under argon, oxygen and vacuum environments respectively. The electrical performance of argon annealed films is significantly improved, while the oxygen annealing is unfavorable to the conductivity of the membranes. The electrical performance of the vacuum annealed sample is just between the argon and oxygen annealed ones. The H-plasma treated sample exhibits a significant improvement of the surface texture while the optical and electrical remain unchanged.2. We designed a new type of crystalline silicon solar cell structure with GZO used as the transparent window and electrode. Acting as the window of collecting carriers, GZO can reduce the high contact resistance caused by the carrier lateral movement, thus reducing the use of the expensive silver gate electrode and increasing the effective light area. Therefore, the new structure can improve the efficiency of solar cell and reduce the cost. Then, considering that the back electrode needs to be annealed at high temperature under the commercial method, the annealing treatment was conducted and the influence on the GZO/Si, back electrode contact and battery performance was analyzed and discussed. After that, we improved the battery structure design by adding an ITO buffer layer. The open circuit voltage, short-circuit current density and battery photoelectric conversion efficiency are increased significantly.