Effect of hydrogen peroxide concentration on surface micro- roughness of silicon wafer after final polishing

摘要

The effect of hydrogen peroxide (H_2O_2) concentration in alkaline slurry on the surface micro-roughness of final polished silicon wafer was investigated. The root mean square roughness (RMS) reached minimum with H_2O_2 when the concentration is 0.05 wt%. Meanwhile, the contact angle of the polished surface was decreased to 21°. This decrease was attributed to enhanced chemical reaction in the CMP process. Electrochemical impedance was measured to explore the variation with addition of H_2O_2 in the reaction process of silicon erosion. Based on the measurements, a mechanism was suggested to explain the phenomenon in combine with the coefficient of friction force in the chemical mechanical polishing (CMP) process. ©2011 Elsevier B.V. All rights reserved.