Communication—Effect of Hydrogen Water on Ceria Abrasive Removal in Post-CMP Cleaning

Abstract

In the present study, hydrogen water was applied to ceria abrasive removal in post-CMP cleaning. The surface of the ceria abrasive was reduced by the hydrogen water from the Ce 4+ to Ce 3+ state. Reduction of the ceria abrasive can weaken the bonding between ceria and the SiO 2 wafer surface. X-ray photoelectron spectroscopy (XPS) and UV–visible observations were utilized to reveal the reduction from Ce 4+ to Ce 3+ by hydrogen water. Thus, the remaining ceria particles and Ce-ion concentrations were reduced by 70% and 63%, respectively.