Beginning with the discovery of Seebeck, thermopiles have come increasingly under the spotlight of commercial infrared sensing. The constantly growing interest has motivated us to write an overview of micromachined thermopiles. The first part deals with the Seebeck effect and discusses the most important physical parameters. In the second part, the most important material systems, techniques and micromachined structures are discussed on the basis of different examples. We explain the motivation behind miniaturized thermopile detectors and give a functional explanation of physical interrelations. Finally, different applications are presented and discussed in terms of their future potential.
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