Optimization of Antireflection Film Structures for Surface-Passivated Crystalline Silicon Solar Cells

Spectroscopic ellipsometry has been utilized to measure complex refractive indices of TiO2 and SiN(x):H antireflection films. The indices of the films are found to vary with measurement wavelength and sample preparation conditions. Using the spectroscopic refractive indices, measured surface reflection spectra are found to coincide with calculated ones. The limit short-circuit current density values for surface-passivated, flat and V-grooved cell structures are calculated and compared as functionS Of SiO2 and antireflection film thicknesses. The maximum value is calculated to be 44.8 mA/cm2 for MgF2/SiN(x):H/SiO2-Coated, V-grooved surfaces with SiO2 thicknesses less than 10 nm. The realizable conversion efficiency is estimated to be 24.3% at the rear surface recombination velocity of 10 cm/s.