Micro-Raman thermometry of thermal flexure actuators

Abstract

Micro-Raman spectroscopy has proven to be a valuable tool for obtaining temperature measurements in active semiconductor and MEMS devices. By using the temperature-calibrated response of the polysilicon Raman signature, we have obtained spatially resolved temperature measurements of U-shaped electro-thermal actuators. Both the peak position and the line width of the characteristic Raman peak have been used as temperature metrics. The measured thermal profiles are further compared to numerical models of the electro-thermal response of the devices as designed and fabricated. The obtained thermal profiles are in qualitative agreement with published modeled thermal profiles of similar devices and are within 15 °C of our modeled profiles. These measurements represent the first reported experimental temperature profile measurements for flexure type actuators and can be used to validate the existing models. Moreover, the comparison of line width and position-based temperatures are in good agreement, differing slightly over the flexure regions of the device.