Fabrication of micro thin film thermocouples
K. Miyazaki, T. Takamiya, H. Tsukamoto
Department of Biological Functions and Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu 808-0196, Japan
We have 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 0.3mm 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 mm spatial resolution, which is finer than that of an IR-microscope.