A micro thermal switch with a stiffness-enhanced thermal isolation structure

Abstract

A solid-contact-type thermal switch requires both high contact force and high thermal isolation, but they are in tradeoff relation. This study demonstrated a novel stiffness-enhanced thermal isolation structure, which can generate high contact force but does not increase heat loss. The stiffness of parylene beams is multiplied by that of silicon stiffening beams, which apply rotational constraint to the parylene beams to reduce the equivalent length of the parylene beams. The stiffening beams are designed as they cause no additional heat loss. The silicon stiffening beams increased the stiffness of the parylene beams by a factor of 1.6, and the unnecessary thermal conductance was still as low as 3.7 × 10−5 W K−1.