Investigation of Source-Based Scratch Formation During Oxide Chemical Mechanical Planarization

The formation of scratches on silicon dioxide surfaces during chemical mechanical planarization in the semiconductor manufacturing process is a significant concern, as it adversely affects yield and reliability. In this study, scratch formation during CMP processing of the oxide surface was examined. The shapes of the resulting scratches were classified into three types: chatter mark type, line type, and rolling type. Chatter mark types were further subdivided into line chatter, broken chatter, and group chatter based on the shape. The effect of three different scratch sources (viz., pad debris, dried particles, and diamond particles) on scratch formation was comprehensively investigated. Chatter-mark-type scratches are predominant in the presence of agglomerated particles and pad debris. Group chatter marks are caused by the addition of pad debris. Unique scratch formation was observed on the wafer with different scratch sources. In particular, multiple-line-type scratches were observed in the presence of diamond particles.