Mapping thermoelectric power of semiconductor junctions with nanometer resolution

Ultra High Vacuum (UHV) Scanning Thermoelectric Microscopy (SThEM) method has been developed to probe the local thermoelectric power of semiconductor nanostructures. When applied to a p-n junction, this method reveals a nanometer-scale abrupt polarity change of the thermoelectric power across the junction. Since the thermoelectric power correlates with the electronic structure, the SThEM allows for nanoscale profiling of the bandstructure and carrier concentrations of homo- and hetero- junctions that constitute the fundamental building blocks of electronic, optoelectronic, and thermoelectric devices.