Effect of corrosion inhibitor, 1H-benzotriazole (BTAH), on particle adhesion in Cu CMP

Abstract

The adhesion force of silica and pad particles on Cu wafer surfaces were theoretically and experimentally investigated in slurry solutions of different pHs with and without the addition of a corrosion inhibitor, 1H-benzotriazole (BTAH). Isoelectric point (IEP) of pad particles was measured to be around 3. Pad particles showed a lower adhesion force in DI water than silica, however resulted in a higher force when BTA was added in DI water. The magnitude of adhesion force of pad particles increased as a function of BTA concentration. The lowest zeta potential of silica particles was measured when 0.01 wt% of BTA was added in DI water. A higher adhesion force was measured on silica particles at pH 3 with the presence of BTA. The increase of pH to neutral to alkaline significantly reduced the adhesion forces of both silica and pad particles © 2005 The Electrochemical Society.