Modeling and minimization of intercascade thermal resistance in multi-stage thermoelectric cooler

The problem of achieving highest temperature difference ΔT in cascade thermoelectric cooler (TEC) is solved with consideration of intercascade thermal resistance. The model of three-dimensional heat spread in substrates is considered. Existence of substrate optimum thickness corresponding to highest ΔT is established. It is shown that correct choice of substrate configuration permits to receive considerable increase in TEC efficiency. In particular, it concerns short-legged TECs having extremely high heat flux densities