Growth and Defects in Cast‐Mono Silicon for Solar Cells: A Review

Cast‐mono silicon (CM‐Si) is a promising substrate to fabricate cost‐effective photovoltaic (PV) wafers used for solar cells with higher efficiency compared with conventional cast multicrystalline silicon (mc‐Si) due to its high throughput and good ingot quality. However, the unavoidable appearance of defects like dislocation, subgrain boundaries, impurities, multicrystallization, and twins, seriously limits its mass‐scale applications in the PV industry. In this review, the growth characteristics of the CM‐Si method are introduced first. Then, the attention is focused on the defects in CM‐Si. Other issues related to production costs that restrict the development of CM‐Si are also addressed in detail, such as seed cost and recycled seeds, n‐type CM‐Si, and large‐size CM‐Si. Finally, a conclusion is made and the prospects are given about the CM‐Si technique.