Method for depositing double-sided PERC battery back film by using flat plate type PECVD equipment

The invention discloses a method for depositing a double-sided PERC battery back surface film by using flat plate type PECVD equipment. The method comprises the following steps: S1, depositing an aluminum oxide film on the back surface of a silicon wafer; S2, depositing a silicon oxynitride film on the back surface of the silicon wafer, wherein S2.1, vacuumizing a reaction cavity of the flat platetype PECVD equipment to 0.3 mbar or below, and then heating the reaction cavity; and S2.2, introducing process gas into the reaction cavity, and guiding microwaves generated by 1-2 pairs of microwavegenerators into the reaction cavity; and S3, depositing a silicon nitride film on the back surface of the silicon wafer, wherein S3.1, vacuumizing the reaction cavity to 0.3 mbar or below, and then heating the reaction cavity; and S3.2, introducing process gas into the reaction cavity, and guiding microwaves generated by multiple pairs of microwave generators into the reaction cavity. The methodhas the advantages of high