Patent ID: 7033000

Claim:
A thermal actuator for a micro-electromechanical device comprising: (a) a base element; (b) a cantilevered element including a thermo-mechanical bender portion extending from the base element to a free end tip residing at a first position, the thermo-mechanical bender portion including a first deflector layer constructed of a first electrically resistive material having a large coefficient of thermal expansion, a second deflector layer, and a barrier layer constructed of a dielectric material having low thermal conductivity wherein the barrier layer is bonded between the first deflector layer and the second deflector layer, the thermo-mechanical bender portion further having a base end and base end width, w b , adjacent the base element, and a free end and free end width, w f , adjacent the free end tip, wherein the base end width is substantially greater than the free end width; (c) a first heater resistor formed in the first deflector layer and adapted to apply heat energy having a spatial thermal pattern which results in a first deflector layer base end temperature increase, ΔT 1b , in the first deflector layer at the base end that is substantially greater than a first deflector layer free end temperature increase, ΔT 1f , in the first deflector layer at the free end; and (d) a first pair of electrodes connected to the first heater resistor portion to apply an electrical pulse to apply a pulse of heat energy having the spatial thermal pattern to the first deflector layer, resulting in a thermal expansion of the first deflector layer relative to the second deflector layer and deflection of the cantilevered element to a second position, followed by restoration of the cantilevered element to the first position as heat diffuses through the barrier layer to the second deflector layer and the cantilevered element reaches a uniform temperature.