Design, Fabrication, and Characterization of High-Stiffness Suspended Microcalorimeters With Nanowatt Power Resolution

This work presents the design, fabrication, and characterization of innovative suspended microcalorimeters tailored for nanoscale heat transfer studies. These devices address the critical trade-off between thermal resistance and stiffness-key factors for achieving nanowatt power resolution while withstanding near-contact forces. By employing a novel three-dimensional U-beam structure, the microcalorimeter achieves a thermal resistance of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(1.555 \pm 0.002)\times 10^{6}$ </tex-math></inline-formula> K/W and a stiffness of 52.5 N/m. This design enables a power resolution of 8.4 nW in DC mode, making it highly suitable for exploring nanoscale heat transfer phenomena across sub-nanometer gaps and atomic junctions. The performance of these devices opens new experimental possibilities in the field of heat transfer at the nanoscale. [2024-0194]