In this research, new thick film screen-printed ceramic microsensors have been proposed, developed, and characterized as discrete devices for high temperature applications and as sensors for smart ceramic packaging applications.;In realizing thick film ceramic microsensors, a new substrate fabrication technique using thick film screen-printed sacrificial layers to create ceramic diaphragm microstructures has been developed. Previously reported ceramic microsensors were primarily focused on Low Temperature Co-Fired Ceramic (LTCC) substrate fabrication technology, but this new thick film substrate fabrication technology offers many advantages over LTCC. The main advantage is screen print selectable cavity airgap distance and diaphragm thickness.;A ceramic cavity microstructure has been designed and fabricated. In order to evaluate the limitations of sensors types that can be produced with this new substrate fabrication technique, the ceramic cavity was fully characterized for hermeticity.;Ceramic capacitive pressure microsensors have been fully developed and realized in this work. The pressure microsensor design, simulation, fabrication and characterization have been completed. The pressure microsensor shows excellent pressure sensitivity.;To demonstrate the flexibility of this microfabrication technique, a piezoresistive sensor was also designed, fabricated and characterized.;Additionally an integrated substrate that consisted of both types of sensors---capacitive and PZR was fabricated and characterized. This developed capability of fabricating multiple types of sensors with thick film enables smart ceramic packaging. This capability allows monitoring of the microelectronic module's environment and permits compensation where necessary to maintain device reliability. To demonstrate this smart ceramic packaging capability, a prototype microelectronic module containing a capacitive pressure microsensor was created in this work. Monitoring of an imbedded pressure microsensor would indicate loss of package hermeticity and would enable device environment recovery methods.;In conclusion, new ceramic capacitive pressure and piezoresistive stress microsensors have been developed utilizing a new thick film substrate fabrication technique. The new thick film sensors and fabrication technique can be used to manufacture stand-alone discrete sensor devices for high temperature harsh environment applications. Additionally, the fabrication technique can be utilized to create imbedded sensors in the thick film microelectronics module substrate for a wide variety of high reliability smart ceramic packaging applications.
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