Trajectories, diffusion, and interactions of single ceria particles on a glass surface observed by evanescent wave microscopy

Abstract

Abstract

3D trajectories and diffusion of single ceria particles near a glass surface and their removal

“…Two entirely different particle motions of single ceria particles in 2D (x-y) plane were observed at pH 7 [12]. As explained above, the motion of particle 1 was similar to the confined motion that was observed at pH 3 and 5.…”

“…In Fig. 3, the time evolution of these positions can be visualized from the color scheme that changes gradually from red initially (t = 0) to blue at t = 20 s. The movements of single ceria particles at pH 3 and 5 are confined to a relatively small area of 15 × 15 nm 2 and 30 × 30 nm 2 , respectively, due to strong attractive electrostatic and van der Waals forces (zeta-potentials of ceria particle at pH 3 and 5 are 70 and 50 mV, respectively, and that of SiO 2 film is −20.0 mV) [12]. The isoelectric point (pH IEP ) of the glass (SiO 2 ) film is 2.0, resulting in a negatively charged glass surface in the pH range we are interested in.…”

“…Similarly, while QCM-D is useful for monitoring the real-time adsorption/desorption behavior of particles on surfaces (i.e., adsorption/desorption rates and their amounts), it provides limited information on the movements of particles on the surface and their interaction energies. We recently reported that evanescent wave (EW) microscopy, also known as total internal reflection microscopy (TIRM), is a powerful tool to directly measure interactions between ceria particles (d mean ∼140 nm) and glass surfaces [12]. Our home-built EW microscopy setup and a schematic of the acquired data and analysis are shown in Fig.…”

“…Summary of D 2D and D 3D of ceria particles near a glass surface at pH 3, 5, and 7 obtained from their respective MSD data as a function of lag time τ. D 2D values are from our previous paper[12].…”

A review on chemical and mechanical phenomena at the wafer interface during chemical mechanical planarization

“…Kim et al reported that the change (ΔpH) in the pH of silica and ceria slurries as the temperature increased from 20 to 90°C was ∼1.0 and ∼1.3, respectively [116,119]. It is well known that a change in pH of slurry has a significant influence on the particle-wafer interactions [123,124]. Also, the solubility of oxygen in water decreases with increasing temperature [125].…”