Design, fabrication, and analysis of double-layer antireflection coatings (ARC) for industrial bifacial n-type crystalline silicon solar cells

Monocrystalline silicon-based, n-type front and back contact (nFAB) solar cells are gradually attracting more interest from the photovoltaic industry, due to their good bifaciality and high efficiency potentials. To further improve the conversion efficiency, nFAB solar cells need to make better use of the solar spectrum. Conventional single-layer SiNx antireflection coating (ARC) tends to have a high reflection loss for ultraviolet photons. Thus, in this work, we prepare a double-layer ARC structure made of SiNx/SiOx stack, deposited by the plasma-enhanced chemical vapor deposition method. We investigate the effects of double-layer ARC through simulation and experimental studies by fabricating bifacial nFAB cells. The results show that the implementation of a double-layer ARC helps to greatly reduce front reflection in short wavelength, and thus allow for improvement of the photocurrent by up to 0.3  mA/cm2. As a result, the average cell efficiency of nFAB solar cells increases by absolute ∼0.2%.