Analysis of Electrostatic Adhesion and Detachment of a Nonuniformly Charged Particle on a Conducting Plane

This paper presents the analysis of electrostatic adhesion and detachment of a charged, dielectric particle resting on a conducting plane. We have studied the effects of particle dielectric constant and the nonuniform charge distribution on the force acting on the particle. Charge on the particle surface is assumed to be smoothly varied and (a) concentrated at the bottom pole or (b) concentrated at the top and bottom poles. The analysis utilizes the method of multipole images to obtain accurate values of the electric field, and determines the electrostatic force from the stress on particle surface. Compared with the force on a uniformly charged particle having the same total charge amount, the analytical results show that the force is significantly enhanced by both kinds of nonuniform charge distribution treated in this work, and is particularly strong when charge is highly concentrated at the bottom pole. It is found that electric field in a limited range must be applied in order to detach the particle from the conducting plane. The electric field necessary for detachment depends strongly on the dielectric constant and the distribution of charge on the particle. The detachment becomes difficult for a particle with charged distributed at the bottom pole, and may be hardly possible if the dielectric constant is too high.