Thermoelectric Materials in MEMS and NEMS: A Review

A review of the basic physics and technology related to thermoelectric MEMS and NEMS devices is proposed, with particular concern to the use and engineering of thermoelectric materials in such devices, and the connection between thermoelectric material properties and device theoretical performance limits. To this purpose, physical models of idealized thermoelectric microsensors and thermoelectric generators are discussed to derive a quantitative relationship between the thermoelectric figure of merit of the materials used in building the devices and their performances. Moreover, the state of the art of fabrication technology for thermoelectric MEMS is examined in an historical perspective, from the early years to the most recent findings related to the possible use of nanostructured silicon and LD thermoelectric materials as new building blocks for this kind of devices.