Abstract: Due to a large number of H atoms,the SiOxNyfilm prepared by PECVD has shown excellent surface passivation performance.By inserting a layer of SiO_xN_y film between the Al₂O₃/SiN_x rear passivation structure of PERC solar cells,Al₂O₃/SiO_xN_y/SiN_x is formed,which can avoid the negative effect of the fixed positive charge carried by SiNxon the negative charge field passivation effect of Al₂O₃.As a result,the silicon minority carrier lifetime increased from 130μs to 162μs,and the cell conversion efficiency increased by 0.09%.The LID of the PERC cell based on Al₂O₃/SiO_xN_y/SiN_x rear passivation structure was also improved,decreasing from 1.83%in the control group to 1.09%in the experimental group.