Thermal characterization of thin film superlattice micro refrigerators

Micro refrigerators based on thin film SiGe/Si superlattices are investigated. Cooling performance of 2.7 degrees at room temperature and 10.8 degrees at 200 C has been measured. Cooling characterization was done using micro thermocouples, and also with the use of visible wavelength thermoreflectance method. Reflectance images of the temperature distribution are presented with spatial resolution better than traditional infrared cameras.