| Cu（In,Ga）（S,Se）2（CIGS） thin film solar cells, have got the highest efficiency up to 21.7%, which have great potential in the future.The main deposition methods of the CIGS thin film include vaccum method and nonvaccum method. Unlike the complex and high cost vacuum method, the nonvaccum methods have the advantages of simple and low-cost, which have been studied widely. Mitize’s group used the hydrazine solution method to fabricate the CIGSSe solar cells and the highest efficiency of 15.2% had been achieved. However, the hydrazine is so toxic and explosive that it can not suitable for the mass production. Therefore it is urgent to find non-hydrazine solvent.There are some progresses in the nonhydrazine mothods. But there are still some problems to be solved:（1） the common solvent can not dissolve the metal chalcogenides,（2） the molecular precursor solution can not avoid introduce unpurity elements, such as chlorin, oxygen etc.,（3） there are small-grained layer with carbon residue. In order to solve these problems, we firstly used 1, 2-ethanedithiol and 1,2-ethylenediamine mixture solvent to fabricate CIGSSe and CIGSe thin film solar cells, and got the power convention efficiency of 11.8% and 11.4% respectively. In this paper, the main works are as follows:1. Though investegating the properties of 1, 2-ethylenediamine, optimizing the volum ratio of 1,2-ethanedithiol and 1,2-ethylenediamine in the mixture solvent and the different pretreating tempearature,we succusfully got the CIGSSe procure solution. Then by optimizing the amount of selenium power, the concentration of the procure solution, the rate of heating, different ways of selenization, we got the large grained CIGSSe thin film.2. Using 1, 2-ethanedithiol and 1, 2-ethylenediamine mixture solvent, and Cu2 S, In2Se3, Ga, Se as the metal sources to form the CIGSSe precure solution, the prepared CIGSSe thin film was abtained by spin coating/sintering. The large grain CIGSSe thin film was got after the selenization though the rapid thermal process（RTP）. In order to investgate the impact of the film’s thickness on the grain growth,different thicknesses of films were deposited by spin coating different times. Based on the thin films of different thickness to fabricate solar cells, we got the highest efficiency when spin coating 8 times. After optimizing, a power convention efficiency of 11.8% was achaived.3. In order to be more simply and precisely to control the composition of the thin film, elemental Cu, In, Ga, and Se were chosen to be dissolved in the 1, 2-ethanedithiol and 1, 2-ethylenediamine mixture solvent to fabricate pure selenide CIGSe thin film solar cell, and the efficiency of 9.5% had been obtained.However, the CIGSe absorber layer had a two-layer structure with the large grain on the top and small grain at the bottom. After the selenization process of a rapid thermal processing（RTP）, the large-grain throughout the absorber layer was successfully obtained. Based on high-quality CIGSSe absorber layer, the encouraging power conversion efficiency of 11.4% has been achieved. |
