Metal contact for chip packaging structure

摘要

A chip packaging structure and packaging method. The packaging structure comprises: a semiconductor substrate; a metal pad provided inside the semiconductor substrate; an insulating layer provided on the semiconductor substrate, the insulating layer having an opening for exposing the metal pad; a sub-ball metal electrode provided on the metal pad; a solder ball provided on the surface of the sub-ball metal electrode, the solder ball having a first apron structure and the first apron structure covering partial metal pad on the periphery of the bottom of the under-ball metal electrode. The chip packaging structure of the present invention enhances the adhesion between the solder ball and the metal pad, and improves the reliability in chip packaging.

主权项

1. A chip package structure, comprising:
a semiconductor substrate; a metal pad inside the semiconductor substrate; an insulating layer on the semiconductor substrate, the insulating layer having an opening exposing a first surface of the metal pad; a sub-ball metal electrode on the first surface of the metal pad, wherein the sub-ball metal electrode partially covers the first surface; a solder ball encompassing the sub-ball metal electrode, wherein the solder ball comprises a first portion extending from the bottom part of the sub-ball metal electrode along directions substantially in parallel with the first surface, such that the first portion of the solder ball covers at least a part of the first surface which is not covered by the sub-ball metal electrode; and a covering layer disposed between the solder ball and the sub-ball metal electrode, and between the solder ball and the first surface of the metal pad, wherein the covering layer is a stacked structure comprising an anti-diffusion layer and a wetting layer, wherein the anti-diffusion layer is disposed on the surface of the sub-ball metal electrode and has a first apron structure, and the wetting layer is disposed on a surface of the anti-diffusion layer and has a second apron structure.