The micro-meter-sized plastic asperities by AC electric field for Poly-vinyl chloride solvent

Abstract

In order to create an inexpensive micrometer-sized plastic asperities, a polyvinyl chloride solvent dissolved in acetone was prepared so that the solvent droplet was put on silicon substrate and placed between parallel plate electrodes (the gap was 5 mm). The effects of concentration, DC/AC and their combination voltage on the creation of micrometer-sized plastic asperities were clarified. As a result, asperities with a height of more than 10 μm were observed from a solvent concentration more than 2.51 mg/ml. It was found that the asperities height increased linearly from around 10 μm to 14 μm with the applied voltage of 0.1 kV to 2.0 kV between the parallel plate electrodes. The effect of DC or AC of 2.0 kV on asperities height and number per unit area were conducted, then the height of asperities decreased from 14 μm to 10 μm when frequency was applied to 11 Hz. To confirm the effect of applying AC voltage on motion of the solvent droplet, high-speed camera observation was carried out. It was revealed that the droplet oscillated by applied AC voltage between parallel plates. The dimensionless height of the droplet increased and reached a maximum at AC 11 Hz. Finally, to clarify the effect of the initial voltage application method on the formation of asperities, a voltage was applied between the parallel plate electrodes under the conditions of DC/AC and no voltage for an initial evaporation time of 3 min. By applying AC 11 Hz during solvent evaporation period, it was clarified that the asperities dispersed most on the surface, then variations in asperities height were reduced.

Keywords

• electric field
• micro-plastic asperities
• polyvinyl chrolide
• esem
• ac and dc voltage