| In recent years, the research and production of thin film solar cells are the focus in the photovoltaic field. For one thing, the enhancing efficiency, carrying out large-scale manufacture, reducing price are main topics of developing the current thin films solar cells. For another, a looking for new semiconductor materials and fabrication technologies to investigate the new generation of solar cells is also an important aspect. Therefore, the main purpose of this article is to develop some new semiconductor thin films used for thin solar cells, actually, two kinds of the thin films have been researched.1. AlSb films that can be used as the absorption layer in solar cells have been studied. AlSb polycrystalline thin films have been fabricated by two methods: vacuum co-evaporation and magnetron sputtering. The structural, morphology, optical and electrical properties of the films have been studied in detail. It has been found that some approximate results are obtained from the films the two different deposition methods. For example, before annealing, only an amorphous phase is detected for the as-deposited films, but after annealing at 540℃for 30 min the AlSb thin films have become polycrystalline ones characterized by cubic phase with (111) preferred orientation, had an optical band gap about 1.60eV and showed semiconductor behavior in electrical properties.Compared with vacuum co-evaporation, magnetron sputtering is more expensive, and needs a special target with a defined surface ratio of Al and Sb. The surface ratio must be defined before from experiments. Nevertheless. once the surface ratio between Al and Sb of target is correct, magnetron sputtering can be a better technology because it can supply higher energy to help Al and Sb into a compound.2. In order to optimize and improve the performance of CdTe/CdS solar cells, a high-resistance transparent layer has been used as a blocking layer between the transparent conducting oxide and CdS layer. In this article, the undoped SnO2 thin films have been prepared by magnetic sputtering with the metallic Sn target and Ar/O2 plasma. The effects of oxygen concentration and thermal treatment on the properties of undoped SnO2 films have been investigated systematically. The as-deposited films are amorphous in structure. After thermal treatment, the samples deposited with 12～34％of oxygen concentration become polycrystalline thin films with a single phase of tetragonal structure. However, SnO phase is found in the films when O2 concentration is 6％. The optical band gaps of the films annealed are in the range of 3.79 eV to 3.92eV. Their room temperature resistivity is smaller than that of the as-deposited films. It has been found that the room temperature resistivity and optical band gap increase with oxygen concentration. The results indicate that 22～30％O2 concentration is the best condition for deposition of SnO2 thin film with high resistance. The carder concentration and mobility of films(22～34％O2 concentration) annealed are in the range of 4～8×1018cm-3 and 2～5 cm/(V·s), respectively. An abnormal conductivity dependence on temperature is observed at about 350K for films as-deposited. The behavior would be probably resulted from the effect of surface oxygen adsorption.
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