Self-powered IC-compatible DC bias for electrostatic resonators

Electrostatic micro actuators require DC bias, for electromechanical coupling. This paper presents an IC compatible self-powered voltage bias generator that uses radioactive /sup 63/Ni thin film and a tunneling oxide-diode. The relatively high voltage bias (10-20 volts) is achieved, by charging a tunneling oxide diode with electrons from a beta particle-emitting thin film. Constant voltage is obtained when the rate of beta particle collection equals the rate of electrons leaking through the oxide diode. Shifts in a clamped-clamped beam resonator are measured as the bias voltage is applied under the resonator.