Cleaning surfaces from nanoparticles with polymer film: impact of the polymer stripping

Abstract

The removal of nanometric particles constitutes one of the main challenges for the Integrated Circuits manufacturing. A solution based on the polymer coating and removal without substrate consumption is described and its performances are evaluated. In our experiments, 60 nm SiO2 particles and 40–200 nm Si3N4 particles are used to contaminate Si wafers. Two polymer removal methods are compared, one is purely based on a chemical action while in the other one a chemical and a physical actions are coupled. We demonstrate that a physical action is required to remove particles. The process shows high Particle Removal Efficiency (PRE) up to 87% independently of the particle size and nature. The PRE stays at a constant value, around 85%, for 3 decades of aging time, but the particle removal is not uniform on all the wafer. Keywords: Polymer, Particle removal efficiency, Contamination, Particle size, Aging