Patent ID: 8535967

Claim:
A method for etching a diaphragm pressure sensor, said method comprising: etching a diaphragm at a selective portion of a substrate with an epitaxial etch stop layer utilizing a deep reactive ion etching process to thereafter orient said diaphragm at an angle with respect to said substrate to avoid an uncertainty in a strain field of said diaphragm; configuring an anisotropic portion on said diaphragm via an etch finishing process to optimize thickness and a size of said diaphragm and provide an enhanced diaphragm structure capable of being utilized across a wide range of pressure sensing applications; and comprising locating at least one piezoresistor on said diaphragm in order to detect said strain due to an applied pressure on said diaphragm; wherein configuring said anisotropic portion on said diaphragm via said etch finishing process further comprises etching said substrate with a doped epitaxial layer utilizing said etching finishing process to stop on said doped epitaxial layer for a time sufficient to locate a diaphragm edge of said diaphragm in a precise location relative to a location of said at least one piezoresistor on said diaphragm.