Chip preparation method

The invention discloses a chip preparation method. The chip preparation method comprises the following steps: S1, preparing a substrate; forming a bottom electrode on the front surface of the substrate; forming a piezoelectric layer on the surface, away from the substrate, of the bottom electrode; s2, performing patterning on the piezoelectric layer; s3, the surface, away from the substrate, of the patterned piezoelectric layer is coated with photoresist; removing the redundant photoresist, and reserving the patterned structure of the piezoelectric layer and the photoresist in the longitudinal projection area range of the patterned structure; s4, a top electrode is formed on the surface, away from the substrate, of the piezoelectric layer filled with the photoresist, and the surface of the piezoelectric layer and the surface of the photoresist are coated with the top electrode; s5, removing the residual photoresist, and removing the top electrode coated on the surface of the photoresist; s6, etching the back