Reflectance of Sub-Wavelength Structure on Silicon Nitride for Solar Cell Application

摘要

In this study, reflection properties of sub-wavelength structures (SWS) on silicon nitride (Si{sub}3N{sub}4) antireflective coatings are investigated. Numerical calculation of SWS reflection based on a rigorous coupled-wave approach is conducted and compared with the measurement of fabricated samples. We compare the results of single- and double-layer-antireflection (SLAR and DLAR) coatings with SWS on Si{sub}3N{sub}4, taking into account average residual reflectivity over a range of wavelengths, where the solar efficiency is further estimated. A low average residual reflectivity of 9.56% could be obtained for a Si{sub}3N{sub}4 SWS height and non-etched layer of 140nm and 60nm respectively, which will be less than 80nm Si{sub}3N{sub}4 SLAR (～15%) and almost the same as that of a DLAR with 60nm Si{sub}3N{sub}4 and 70nm magnesium fluoride (～10%).