Fabrication of micro-thin film thermocouples

We fabricated thin film thermocouples (TFTCs) to measure temperature distributions at the micro-scale. Nickel film was deposited as the first thermocouple material. Silicon dioxide was then deposited on the Ni film as an insulator. To make the thermocouple junctions, micro-holes were opened by focused ion beam (FIB), and tungsten film was patterned on the insulator as the. second thermocouple material. The thermocouple junctions were 0.5 μm across. We also fabricated a micro-heater near the micro-TFTCs. The heat flux from the micro-heater was estimated by measuring the applied electric power. By using this micro-heater we calibrated the micro-TFTCs without using other thermocouples. With this setup, we have measured temperature distributions with 10 μm spatial resolution, which is finer than that of an IR-microscope.