Application of thermal atomic layer deposited Al₂O₃ in c-Si solar cells

Thermal atomic layer deposited (ALD) Al₂O₃ films are applied at the front and rear sides of PERC-type c-Si solar cells. At the front side, Al₂O₃/SiN_x as a double-layer antireflection coating reduces the reflection loss, and at the rear side, Al₂O₃ film as the passivation layer decreases the surface recombination velocity and enhances the internal reflectance at near-infrared (NIR) band together with SiN_x layer. Due to the improvement in the reflectance combined with a decrease of the surface recombination velocity, the PERC solar cells show an improved J_SC by 0.2 mA/cm² compared with the full-area back surface field cell.