Electrostatic field-induced surface instability

We examine the thermodynamics and evolution of the morphology of a metal surface in the presence of a large electric field. A flat surface is unstable for all finite electric fields E with a critical wavelength proportional to E-1 or E-2 at small and large fields, respectively. The instability wavelength that grows the fastest during surface diffusion-limited evolution scales in the same manner. Such instabilities are important for scanning probe microscopies and are becoming increasingly important in microelectromechanical systems applications as device dimensions are reduced. (C) 2004 American Institute of Physics.