Achieving a high Short Circuit Current Density of 40.9 mA/cm² for Two-Side Contacted Silicon Heterojunction Solar Cells by using SiC-based Transparent Passivating Contacts

A silicon heterojunction solar cell using silicon carbide as front contact is presented, which features the main advantage of high transparency. To enhance this advantage, an optical loss analysis is performed. It is found that reflection losses play an important role for the solar cell, which can easily be reduced by applying an additional MgF2 coating. The deposition of the coating degrades the passivation quality of the contact but can be cured, eventually leading to a certified short circuit current density of 40.9 mA/cm² and efficiency of 23.99%. Afterwards, a roadmap to a theoretical efficiency of 25% is presented.