Using finite element methods and 3D image correlation to model solar cell bowing

Previous efforts aimed at modeling solar cell bowing due to the aluminum back surface field (BSF) have focused on relatively simple two or three layer models. This paper will outline the effort to develop a more sophisticated finite element (FE) model approach. This approach is superior to previous modeling efforts since it allows a more accurate representation of the cell structure and can handle complex geometry like the front surface grid and silver bus bars. The first section of the paper will highlight previous modeling efforts touching on the strengths and weaknesses of the various approaches. The second section focuses on the unique measurement techniques used to quantify actual solar cell bowing. The final section of the paper will concentrate on the model details and the use of the model to gain insight into how the various layer thicknesses (silicon, eutectic, aluminum, etc.) and cell geometry impact cell bowing.