Development of an all-in one wet single wafer process for 3D-SIC bump integration and its monitoring

In this paper we will described an integrated wet process for bump fabrication. The integrated wet process is comprising of a photoresist strip, a copper (Cu) seed layer etch and a titanium-tungsten alloy (TiW) etch. In order to minimize the Cu lateral etch, the Cu seed etch process will be assisted by an optical end-point detection system. The monitoring of the integrated process on 3 different bump densities will also be described in more details.