Simulation and Optimization of an In-plane Thermal Conductivity Measurement Structure for Silicon Nanostructures

Abstract

Silicon-on-insulator based measurement structures have recently been developed to measure the thermal conductivity of nanostructured materials. For example, suspended steady-state measurement structures are often used for measuring the in-plane thermal conductivity of thin silicon films as the heat transfer is confined to the lateral direction. However, few researchers have focused on optimizing the important structural and measurement parameters, such as geometry and applied heater power levels, to ensure accurate measurements. In this article, numerical simulations are first compared with existing experimental data for suspended steady-state joule heating measurement structures with a large suspended region (~10 mm2). Then, a smaller scale (suspended surface area ~500 μm2) structure is developed and optimized for measurement of porous nanostructured silicon materials to maximize the measurement accuracy for the range of expected sample thermal properties.