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In this study, the effect of viscosity on ceria abrasive removal during the buff clean process was investigated. First, a numerical simulation was performed to observe the shear stress on the wafer. The shear stress increased as the viscosity increased. These results imply that the viscosity increases the drag force acting on the abrasives, which can improve abrasive removal. Based on the results of the numerical simulation, the ceria abrasive removal was measured using inductively coupled plasma mass spectroscopy (ICP-MS). The ICP-MS results showed that the increased viscosity improved the cleaning efficiency of the ceria abrasive removal by 70%. In addition, a lowering of the water temperature also resulted in an increase in abrasive removal as the viscosity increased. These results can be used to improve ceria abrasive removal during the buff clean process.

Herein, the tribological behavior of layered few nanometer‐thick MoS2 thin films is evaluated to identify their applicability to an oil‐free solid‐lubrication coating layer. The MoS2 thin films are synthesized using a plasma sulfurization process with optimized steps and conditions derived from a previous study. MoS2 thin films with different thicknesses are heat treated at 400 °C to investigate the effect on their tribological properties. The ball‐on‐disk method is used to observe the friction and wear behavior of the MoS2 thin films, and this test is carried out under an applied load of 0.5 N in an ambient atmosphere (≈23 °C). The coefficient of friction of the unheated MoS2 layers increases rapidly at 32–36 cycles regardless of the thickness. However, the heat‐treated MoS2 films maintain a lower coefficient of friction for more cycles (60–86 cycles). The heat treatment effect effectively increases the wear life of the MoS2 thin film. Based on this result, it is believed that the heat‐treated MoS2 thin films can be potential solid lubricant candidate for micro‐ and nanoelectromechanical systems.

Various methods such as transmission electron microscopy, scanning electron microscopy, dynamic light scattering (DLS), and scanning mobility particle sizer were utilized to measure size distributions for sub-100 nm colloidal silica. Compared to electron micrographs, hydrodynamic diameter of sample is dependent on its concentration from ∼60 nm to ∼90 nm and it is difficult to measure the poly dispersed nanoparticles and analyze its own properties due to limitation of DLS method, whereas, nano nebulizer (NN)-SMPS method distinguished two different size nanoparticles (51 nm and 82 nm) perfectly and is considerably stable to alternations of concentration and dispersity.