An effective method to reduce bump defect is investigated

In this paper, problems and solutions for bump defect due to the stopper-SiCN layer and scrubber are investigated, and the mechanism of the defect by SiCN is clarified. In the 28 nm node flow, it is found that skipping SiCN layer scrubber and increasing NH
₃
flow rate and reducing pressure can effectively eliminate bump defect. In the proposed mechanism, the unsaturated bond suspension bond of Si can easily absorb a large amount of OH
^-
plays an important role in forming bump defect, liquid line condense and residue will be effect on bump defect after scrubber. This paper analyzes this mechanism in detail.