Al2O3/TiO2 double layer anti-reflection coating film for crystalline silicon solar cells formed by spray pyrolysis

Al2O3/TiO2 double layer anti-reflection coating (ARC) film formed by spray pyrolysis was introduced for monocrystalline silicon solar cells as the nonvacuum processing method. The thickness of the Al2O3 layer and TiO2 compact layer was controlled by the volume of deposited precursor solution and confirmed by ellipsometry and scanning electron microscope. The average photovoltaic properties of photocurrent density (Jsc), the open-circuit photovoltage (Voc), the fill factor (FF), and the photo energy conversion efficiency (η) were 37.0 mA/cm2, 590 mV, 0.712, and 15.5%, respectively. A significant improvement on Jsc and η could be confirmed owing to the Al2O3/TiO2 ARC. According to the results of Fourier transform infrared (FTIR) spectroscopy and optical simulation with modeling for the reflectance properties, it was confirmed that C-H-based organics remained after the deposition of thin films.