Several different designs of surface-micromachined pressure sensors have been evaluated for possible application to dynamic pressure testing. The sensors are based on deformable silicon nitride (Si{sub}3N{sub}4) or fine-grained polysilicon diaphragms with polysilicon piezo-resistors. Static and quasi-static pressure tests have been used to evaluate detector sensitivity and linearity as well as susceptibility to temporal drift and hysteresis in response to pressure and temperature cycling. Nonlinear finite element methods have been successfully applied in modeling silicon nitride diaphragm deflection under static loading, capturing all salient characteristics of sensor response as a function of applied pressure. These methods are readily adaptable to structural dynamics simulation of sensor response to dynamic pressure events. Initial tests of the microsensors in a dynamic pressure environment consistently resulted in failure of the frontside contact wire bonds, highlighting critical issues in device packaging. Initial efforts to adapt the existing sensors to a backside contact scheme using laser micromachining and via metallization are described.
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