Reversible thermal interfaces based on microscale dielectric liquid layers

We present a reversible thermal interface that can circumvent limitations of direct solid-solid contacts. A thin continuous layer of a dielectric liquid is formed between two solid substrates to provide a low-resistance heat conduction path. The liquid is initially confined in an array of discrete microchannels and undergoes reversible morphological transition into a continuous film as the loading pressure is increased. We theoretically and experimentally determine the relationship between loading pressure and liquid morphology. The interfaces can achieve thermal resistance comparable to that of solid-solid contacts but at loading pressures orders of magnitude smaller.