Thermal Characterization for Reliability Assessment of Solidly Mounted Resonators

This paper deals with the temperature impact on electrical characteristics of thin film acoustic resonators. Consequences of excessive temperature due to self-heating and harsh environment are investigated. For self-heating aspects, an RF power bench coupled to an infrared camera with a spatial resolution as good as 2 mu/pixels gives us accurate thermal images of structures while submitted to high power. In addition, drifts or resonances in respect to power are properly measured. In a different way, resonator behavior, under small signal, but from low to high temperature is determined above wireless specifications. Complementarily to RF characterizations, a 1-D modeling based on transmission line equations is modified and a way for increasing thermal stability of resonators is proposed