Method for etching material longitudinally spaced from etch mask

Abstract

A micromachining process forms a plurality of layers on a wafer. This plurality of layers includes both a support layer and a given layer. The process also forms a mask, with a mask hole, at least in part on the support layer. In this configuration, the support layer is positioned between the mask hole and the given layer, and longitudinally spaces the mask hole from the given layer. The process also etches a feature into the given layer through the mask hole.

Description

technical field [0001] The present invention relates generally to MEMS devices, and more particularly, the present invention relates to processes for forming microfabricated devices. Background technique [0002] Microelectromechanical systems ("MEMS") are used in a growing number of applications. For example, MEMS are currently implemented as gyroscopes for detecting the pitch angle of aircraft, as microphones for use in mobile phones, and as accelerometers for selectively deploying airbags in automobiles. Briefly, such MEMS devices typically have a structure suspended above a substrate, and associated electronics that both sense movement of the suspended structure and communicate the sensed movement data to one or more external devices (for example, an external computer). The external device processes the sensed data to calculate the property being measured (eg pitch angle, incident acoustic signal or acceleration). [0003] As known to those skilled in the art, one com...

AI Technical Summary

Problems solved by technology

However, the complexity of the surface micromachining process generally increases as more layers are added to and subtracted from the substrate

Thick layers (such as rigid backplates in MEMS microphones) present further challenges to the microfabrication process

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