Abstract
An abrasive nanoparticle behavior in chemical mechanical polishing (CMP) process is a three-dimensional (3D) motion near a substrate or reference surface. The height position is a longitudinal distance between the reference surface and nanoparticle, which is a challenge for measuring the height position in a wet condition. Our previous report could estimate the relative height of polystyrene 100 nm particles by applying multi-wavelength evanescent fields, but the absolute height was not confirmed yet. Therefore, in this report, we proposed a design concept for absolute height verification by using the developed nano-step height patterns. The nano-step height was approximately less than hundred nanometers from the reference surface. The nano-step height made from an optical resin that has a refractive index close to water to decrease the scattering light during observing nanoparticles in water. Polystyrene 100 nm particles on the nano-step height were used to estimate the absolute height of nanoparticle. The proposed concept could be used to verify the nanoparticle's absolute height in water, which can be applied to clarify the nanoparticle phenomena during the CMP process in the near future.
