Nanoscale Thermometry Using Point Contact Thermocouples

Probing temperature fields with nanometer resolution is critical to understanding nanoscale thermal transport as well as dissipation in nanoscale devices Here, we demonstrate an atomic force microscope (AFM)-based technique capable of mapping temperature fields in metallic films with similar to 10 mK temperature resolution and <100 nm spatial resolution A platinum-coated AFM cantilever placed in soft mechanical contact with a metallic (gold) surface is used to sequentially create point contact thermocouples on a grid The local temperature at each point contact is obtained by measuring the thermoelectric voltage of the platinum-gold point contact and relating it to the local temperature These results demonstrate a direct measurement of the temperature held of a metallic surface without using specially fabricated scanning temperature-probes