Dry etch release of MEMS structures

Abstract

The present invention pertains to a method of fabricating a surface within a MEM which is free moving in response to stimulation. The free moving surface is fabricated in a series of steps which includes a release method, where release is accomplished by a plasmaless etching of a sacrificial layer material. An etch step is followed by a cleaning step in which by-products from the etch step are removed along with other contaminants which may lead to stiction. There are a series of etch and then clean steps so that a number of “cycles” of these steps are performed. Between each etch step and each clean step, the process chamber pressure is typically abruptly lowered, to create turbulence and aid in the removal of particulates which are evacuated from the structure surface and the process chamber by the pumping action during lowering of the chamber pressure. The final etch/clean cycle may be followed by a surface passivation step in which cleaned surfaces are passivated and/or coated.

Dependencies are inferred from the claim text.