Cascade cryogenic thermoelectric cooler for cryogenic and room temperature applications

A cascade thermoelectric cooler designed to cool to cryogenictemperatures of 30 to 120 K integrates highperformance.backslash.high-ZT Bi.sub.x Sb.sub.2-x Te.sub.3 andBi.sub.2 Te.sub.3-x Se.sub.3 -based super-lattice-structurethin-film thermoelectric devices with a bulk-material basedthermoelectric cooler including plural cascaded cold stages witheach successive cascaded cold stage able to cool to a progressivelylower temperature. Each cold stage in the bulk-materialthermoelectric cooler includes a heat source plate, a heat sinkplate, a p-type thermoelectric, and a n-type thermoelectric.Moreover, the thin-film thermoelectric cooler can have multiplestages in which each stage contains a heat source plate, a heatsink plate, a p-type super-latticed thermoelectric element, and a ntype super-latticed thermoelectric element. By bonding an outputheat source plate on the thin-film thermoelectric cooler to aninput heat sink plate on the bulk-material thermoelectric cooler,the integration of the thin-film thermoelectric with thebulk-material-based thermoelectric yields a cascade thermoelectriccooler wherein the bulk-material-based thermoelectric cooler coolsto 160 K and the thin-film thermoelectric device cools to cryogenictemperatures between 70 and 120 K. Another level of thin-filmsuper-lattice integration can achieve temperatures of 30 K.Alternatively, the integration of a high ZT thin-film superlatticethermoelectric cooler on a multi-staged bulk-material-basedthermoelectric cooler can produce a higher performancenon-cryogenic cooler.