Restoring sputter damage by light soaking in silicon carbide-based transparent passivating contact solar cells

<h2>Summary</h2> Crystalline silicon (c-Si) solar cells with hydrogenated nanocrystalline silicon carbide (nc-SiC:H)-based transparent passivating contact (TPC) achieve enhanced short-circuit current density (<i>J</i>_SC) compared to conventional silicon heterojunction (SHJ) solar cells but suffer from lower open-circuit voltage (<i>V</i>_OC). The <i>V</i>_OC loss is largely due to sputter damage during Sn-doped indium tin oxide window layer deposition. We evaluate thermal annealing for damage mitigation but find limited restoration due to differing thermal tolerances of TPC and SHJ contacts. Instead, a direct heat-assisted intensive light-soaking (LiSo) treatment effectively heals the sputter damage, improving <i>V</i>_OC above 735 mV and achieving a certified efficiency of 24.17% ± 0.29%. Detailed investigation highlights the synergistic effects of light and heat in the LiSo process. Additionally, a damage-restoration mechanism related to hydrogen motion is discussed.