The invention provides a TSV hole bottom medium layer
etching method. For TSV holes with
small hole diameters, the TSV hole bottom medium layer
etching method can reduce TSV hole bottom medium layer
etching difficulty and avoid damage to TSV side wall insulating layer materials in the etching process. The TSV hole bottom medium layer etching method includes the steps of step 1, carrying out back face
thinning on a
wafer comprising an IC device, step 2, manufacturing a TSV hole in a position, corresponding to a
metal bonding pad, of the back face of the
wafer comprising the IC device, step 3, manufacturing a
polymer insulating layer in the TSV hole, step 4, removing the
polymer insulating layer at the bottom of the TSV hole and enabling an
oxide insulating layer at the bottom of the TSV hole to be exposed, step 5, etching the
oxide insulating layer exposed out of the bottom of the TSV hole through wet
processing and enabling the
metal bonding pad to be exposed, and step 6, manufacturing an RDL through
metal connection wires, enabling the RDL and the metal bonding pad at the bottom of the TSV to be connected, and further manufacturing a surface metal bonding pad and slight solder bumps to enable the surface metal bonding pad and the slight solder bumps to be connected with the RDL.