Patent ID: 6058782
Filing Date: 2000-05-09
Classification: G01L

Abstract:
A high temperature pressure transducer comprising:a first substrate fabricated from silicon carbide having on a surface a central active region capable of deflecting and a surrounding non-active region which is more rigid than said active region;a plurality of piezoresistive sensors elements disposed on said active region, of each sensor elements having a given line width;a plurality of generally enlarged contact areas extending from and surrounds said sensor elements on said active region to near the periphery of said first substrate, said contact areas being generally located in said non-active region of said first substrate, each said contact areas having a smaller centrally located contact, each of said sensor elements being coupled to at least two contact areas;an external rim on the periphery coplanar with the contact areasisolation moats for isolating said contact areas from each other and from said periphery of said first substrate, said isolation moats being dimensioned on the order of magnitude of said line width of said sensor elements; a metalized area near the center of each contact each such metalization being of a high temperature capability;a second substrate of silicon carbide having a plurality of apertures extending therethough, each of said apertures aligned with and corresponding to the centrally located metalized contact areas;means for joining said first substrate to said second substrate without contacting said sensor elements thereby providing hermetic seal of said sensor elements; andmeans for sealing said plurality of apertures while providing access to each contact.