Method and apparatus for stress pulsed release and actuation of micromechanical structures

Abstract

Micromechanical parts are freed from a surface of a substrate to which the parts are stiction bonded by applying a pulse stress wave to the substrate that propagates through the substrate and is reflected at the surface to which the micropart is stiction bonded, breaking the bond between the micropart and the substrate surface by a spalling action at the surface. A piezoelectric transducer may be secured to the bottom surface of the substrate such that a voltage pulse supplied to the piezoelectric transducer deforms the piezoelectric element and the substrate to which it is secured to provide a pulse stress wave that propagates through the substrate to the top surface. For microparts that are in contact with but not stiction bonded to the substrate top surface, a pulse stress wave can be applied to the substrate to drive the microparts away from the surface by the rapid displacement of that surface as the pulse stress wave is reflected at the surface. Microparts that are attached to the surface in a way to permit rotation or a translation of movement may be activated by applying a pulse stress wave to the substrate to drive such parts away from contact with the surface into their erected positions.

Dependencies are inferred from the claim text.