Characterization and development of materials for an integrated high-temperature sensor using resistive test structures

This paper reports the application of test structures to the evaluation of tantalum nitride (Ta-N) as a material for integration with high temperature electronics. The test structure fabrication involves the reactive sputtering of Ta-N and its consequent annealing in a vacuum to reach the target specifications of low temperature coefficient of resistance (TCR). A test wafer has been designed to both evaluate the temperature performance of thin films and to study the possibility of integrating different metal films into a single sensing device. The Ta-N resistors resulting from this work have a TCR of -150 ppm/°C which remains stable after 6 hours of annealing at 600°C.