Impact of illumination and metal impurities on parameters of monosilicon solar cells

Abstract

Monocrystalline silicon solar cells were prepared with three kinds of diffusion processes (deep diffusion, one-face diffusion and two-face diffusion), and the current–voltage (I–V) curves were separately measured under dark and illuminated conditions. Based on bidimensional numerical fitting through the explicit expression of the I–V characteristics with Lambert W functions, the intrinsic and extrinsic model parameters of the cells under different circumstances are obtained. For the cells under dark condition, deep diffusion gives the lowest values of both shunt resistance R_sh and series resistance R_s, and all the cells have an ideality factor n larger than 2. Compared with dark condition, illumination reduces all the values of R_sh, R_s and n. In addition, the short circuit current I_sc of the cells with deep diffusion is the lowest, while their open circuit voltage V_oc is the largest. I_sc of the cells with double-face diffusion is the largest, while their V_oc is close to that of the cells with one-face diffusion.

Keywords:

• Solar cells
• I–V characteristics
• Defects and Impurities

This work was partly supported by the foundation of Science & Technology Program of Jiaxing in China (No. 2011AY1037) and the National Natural Science Foundation of China (No. 61306072).