Effect of poly silicon wettability on polymeric residue contamination

Abstract

The adhesion and removal of the polymeric residues were investigated as a function of wettability of the poly Si surface during poly-Si CMP process. An oxidizer can make poly silicon surface more hydrophilic. Adhesion force between pad particle and poly Si wafer decreased and saturated as a function of concentration of oxidant. Much more pad particles with water marks were observed on hydrophobic poly silicon surfaces than on hydrophilic. The mechanism of wettability and high adhesion force of hydrophobic surfaces indicates that the controlling of the wettability of wafer surface played an important role in the adhesion and removal of organic residues on the poly Si surface. The control of poly silicon wettability during polishing could reduce the attraction force of organic particles thus lead to a lower organic defects after CMP. © The Electrochemical Society.