Rear side passivation characteristics of silicon oxy nitride films for high efficiency silicon solar cell

摘要

High quality rear surface passivation is a prerequisite to obtain high conversion efficiency on thin wafers. SiOxNy with low absorbance and variable refractive index inherits the properties of both SiNx and SiO_2 which act as a rear surface reflector. SiO_xN_y layer with low refractive indices ranging from 1.51 to 1.61 was deposited and their chemical composition was analyzed by Fourier transform infrared (FTIR) spectroscopy. With the optimized SiO_xN_y layer the I-V results yielded a short circuit current density (J_(sc)) of 38.7 mA/cm~2 and efficiency of 19.34%, with open circuit voltage (Voc) of 635 mV.