Thermoelectric micro devices:: Current state, recent developments and future aspects for technological progress and applications

Due to their unique expected properties thermoelectric microdevices, thermogenerators as well as Peltier coolers, are of high demand for different applications namely for telecommunication purposes. Thus worldwide efforts are undertaken to expand the technology for thermoelectric devices into the field of typical microsystem technologies including aspects of advanced low dimensional high ZT materials. Favourite material systems are up to now the bismuthtelluride (V-VI) compounds and the silicon/germanium (IV-IV) alloys. Recent results prove the capability to implement low dimensional material of both material systems into microsystem devices and demonstrate wafer based microelectronic technologies for the fabrication of thermoelectric devices even for the non CMOS bismuthtelluride related compounds. Thus this survey will present the state of the art [1-9] in a summary of recent results together with an more extended description of the MicroPelt(R) approach as an example for a wafer based fabrication concept close to microelectronics manufacturing. Strengths and weaknesses of the different presented technological concepts will be discussed under some viewpoints.