MEMS for characterization of thermal conductivity in thin films and two-dimensional materials

Inhalt:
In this work, we developed a micro-electro-mechanical system (MEMS) to measure the in-plane thermal conductivity of thin films and two-dimensional (2D) materials. The platform consists of Platinum-based resistive temperature devices (RTDs) arranged in linear and spiral staggered configurations at different distances from a microheater in the center as a heat source. The RTDs are designed in a four-point contact resistance measurement configuration. The microheater and the RTDs are assembled on a silicon nitride (SiN) membrane to minimize the thermal transport perpendicular to the surface. The SiN membrane is created by wet-chemical etching the silicon wafer from the backside using potassium hydroxide. We developed an electronic measurement setup, which currently allows software-controlled calibration and steady-state measurement of the devices. Preliminary results of the measured temperature profile on the membrane with and without a Parylene C layer are presented.