パッド表面分析による研磨メカニズムの研究(第２報)

−ドレッシング無しの研磨過程におけるパッド表面状態の解析−

抄録

In order to evaluate pad surface condition to stabilize removal rate in oxide-CMP(Chemical Mechanical Polishing), chemical modification on pad surface was evaluated under no conditioning process as an opposite phase. As the result, the pad surface was hydrolyzed in accordance with no conditioning process proceeding. Silanol groups contained in slurry or generated by oxide polish combined with polarized molecules in poly-urethane material of the pad by a hydrogen bond. The pad surface stacked silica component with the silanol groups leads to removal rate drop due to inhibition of chemical reaction to polish oxide film. The pad treatment by means of the following Si substrate polish contributed to removal rate recovery of oxide film. The behavior suggested that not only geometrical factor of pad surface such as asperity or roughness but also chemical factor of pad surface such as hydrophilicity or hybrid formation has an influence on keeping removal rate. The removal rate recovery of oxide film after Si substrate polish was attributed to silanol groups elimination on pad surface which was caused by condensation between silanol groups on pad surface and hydroxyl groups on Si surface.