The characteristics of glass/TCO/p-a-SiC:H/i-a-Si:H/n-μc-Si:H/Al structure solar cells have been analyzed by a numerical method using Gummel-Sharfetter method. The effects of D-states density in p, i, and n layers on the performance of the amorphous silicon (a-Si:H) based solar cells were analyzed. The buffering effects of the p-mc-Si:H layer between the p-a-SiC:H and i-a-Si:H were elucidated by the numerical analysis, which is to improve the short wave response and the Voc of the cells with a structureof glass/TCO/p-μc-Si:H/p-a-SiC:H/i-a-Si:H/n-μc-Si:H/Al. The improvement of the cell performance by inserting the p-mc-Si:H layer is caused by the reduced Shockley-Hall-Read recombination life time at the p/i interface.
The genetic algorithms were introduced, for the first time, for the optimization of p-, i- and n-layer thicknesses to obtain the highest cell performance in the cell with a structure of glass/TCO/p-a-SiC:H/p-μc-Si:H/i-a-Si:H/n-μc-Si:H/ZnO/Al. From this simulation result, the genetic algorithm was proved to be a time-saving method through simulation number reduction for the optimizaton of the a-Si:H based solar cells. The optimum conversion efficiency of 11.89% was obtained using the genetic algorithm.
A novel structure of glass/TCO/Al/p-μc-Si:H/i-a-Si:H/n-μc-Si:H/ZnO/Al was proposed to reduce the light absorption loss in the p-a-SiC:H layer of the glass/TCO/p-a-SiC:H/p-μc-Si:H/i-a-Si:H/n-μc-Si:H/ZnO/Al structure. Also by using genetic algorithms, the optimum conversion efficiency of 12.51% was obtained.
