Numerical study on various types of stress and dislocation generation in multi-crystalline silicon at various growth stages for PV applications

Photovoltaic (PV) solar cell plays a main role in recent development of green energy technology. Multi-crystalline silicon is an important material with advantages of low-production cost and high conversion efficiency of PV solar cells. Numerical simulation was performed to study the generation of creep stress and formation of dislocations in multi-crystalline silicon at the various growth stages. Computations are carried out using the finite volume method. A 2D numerical approach is successfully used to study the thermal stress and dislocation density in directional solidification silicon. The generation of dislocation and von Mises stresses is calculated by Haasen–Alexander–Sumino model. This model gives the quantitative description of the relationship between plastic deformation and dislocation density. This study is aimed to achieve an advanced understanding of the thermal stress, inelastic creep deformation, and dislocation multiplication in grown mc-Si. The results have shown that the most intensive multiplication of dislocations is occurring at the final growth stage, which may control by the optimize hot zone furnace.