Characteristics of CIGS Solar Cells with different evaporation Ga gradient and Cu content in Multistage

• Main Authors: Ting-Wei Lin, 林碇為
• Other Authors: Nen-Wen Pu
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/zw2hx9

碩士 === 元智大學 === 光電工程學系 === 105 === In this research, the three-stage co-deposition process was proposed by NREL, and CIGS thin films were prepared by three-step and four-step deposition . The CIGS films were deposited on Mo coated soda-lime glass substrate by evaporation system. In the first stage, the composition of Ga / (In + Ga) was controlled to 0.4, and varied the Ga / (In + Ga) to 0.4, 0.35 and 0.3 in the third stage. In the third stage, the composition of Cu/ (In + Ga) was controlled to 0.8, and varied the Cu/ (In + Ga) to 0.8, 0.83, 0.86, 0.89, 0.92, as the variables to observe the fifteen groups of CIGS thin-film devices. The analysis was performed about the structure of absorber layer films, surface properties, optical properties, electrical properties, elemental distribution, and conversion efficiency. The obtained CIGS absorber layer possesses unique equiaxed grain with (112) preferred to orientation by four-step evaporation process. In this experiment, when the composition of Ga / (In + Ga) ratio is 0.8 , the energy gap of the film decreases from 1.18 eV to 1.09 eV with the composition of Ga / (In + Ga) decreasing. When the composition of Cu/ (In + Ga) was increased, the energy gap of the film decreases from 1.18 eV to 1.05 eV, and the defective of compound can be found on the film surface.In this research, the optimal result is that Ga/(In+Ga) was 0.35 and Cu/ (In + Ga) was 0.4 where the solar cell showed the highest efficiency of 10.26%.