Manifestation of the connection between dielectric breakdown strength and contact angle saturation in electrowetting

Limiting phenomena on the electrostatically assisted wetting of dielectric solids by conducting liquids are illuminated by means of computer-aided analysis. The importance of the electrostatic edge effects and their influence on the dielectric properties of the solid is raised to demonstrate that contact angle saturation sets in when the electric field strength locally exceeds the breakdown strength of the dielectric solid where the liquid sits. The proposed argument along with the computed predictions is tested against published experimental measurements showing remarkable agreement. (c) 2005 American Institute of Physics.