Enhanced thermoelectric cooling at cold junction interfaces

We describe a thermoelectric device structure that confines the thermal gradients and electric fields at the boundaries of the cold end, and exploits the reduction of thermal conductivity at the interfaces and the poor electron-phonon coupling at the junctions. The measured temperature-current and voltage-current characteristics of a prototype cold point-contact thermoelectric cooler based on a p-type Bi0.5Sb1.5Te3 and n-type Bi2Te2.9Se0.1 material system indicate an enhanced thermoelectric figure-of-merit ZT in the range of 1.4-1.7 at room temperature. (C) 2002 American Institute of Physics.