Thin film thermocouple technology for real-time, high-temperature (1000C), distributed thermometry spans a wide range of commercial application areas, including semiconductor manufacturing and combustion engine feedback. At present, a lack of suitable high-temperature thin film insulators, required to provide an adhesive interface we well as an electrical and chemical barrier between the substrate and the thermo-elements, severely hinders widespread implementation of this technology. Compounds from the MgO-SiO2-Al203 ternary system offer the opportunity to overcome the limitations of conventional insulators. These compounds are chemically compatible with silicon, have high resistivity at elevated temperatures, and offer a range of coefficients of thermal expansion. Metal organic chemical vapor deposition (MOCVD) of complex oxides is an attractive fabrication method because of its ability to cover large areas with high quality films and, coupled with the ability to coat complex shapes, can conformally encapsulate thin film thermocouples for improved robustness. In Phase 1, MgO and MgAl204 films will be deposited by MOCVD on silicon substrates and fully characterized, including electrical behavior at elevated temperatures. In Phase 2, film performance will be optimized, full encapsulation of thin film thermocouples will be examined, and the deposition process will be extended to insulator films such as Mg2Al3(AISi)5018. COMMERCIAL APPLICATIONS: The potential commercial applications of thin film insulator compounds from the MgO-Si02-Al203 ternary system include high temperature insulators for silicon wafer based thermometry using thin film thermocouples, gas turbine engine thermometry, and barriers/buffer layers for advanced semiconductor devices
