Effects of Friction Modifier Additives on HDD Substrate Defects and Surface Topography during CMP

Abstract

This study investigates the effects of Friction Modifier Additives (FMA) added into the polishing slurry on Aluminium Nickel Phosphorous plated (Al-NiP) Hard-Disk Drive (HDD) substrates surface topography and surface defects during Chemical Mechanical Polishing (CMP) process. It is confirmed that addition of Friction Modifier Additives into the slurry reduces the overall coefficient of friction (CoF) during CMP process. By increasing the FMA concentration in the polishing slurry, the substrate surface topography such as waviness and surface roughness were improved significantly. It also lowered the defects counts especially scratch and sub-micron damage as revealed under Optical Surface Analyser (OSA) and Atomic Force Microscope (AFM) analysis.