Department of Mechanical Engineering
Kenneth E. Goodson
Goodson, K.E., and Asheghi, M., 1997, "Near-Field Optical Thermometry," Microscale Thermophysical Engineering, Vol. 1, pp. 225-235.
Far-field optical thermometry techniqu es hav e spatial resolu tion limited by diffraction to the order of the radiation wav elen gth. We report progress on near-field optical thermometry (NFOT) that targets spatial resolution better than 50 nm. A tapered, single-mode optical fiber scans na ometers above electronic microstructures, which are heated using transient electrical currents. The fiber tip releases about 1 nW of radiation power from a steady probe laser, and the reflected radiation is used to measure the local temperature. Simultaneous electrical resistance thermometry is used to estimate the relative importance of temperature dependent optical properties of the sample and thermal expa sion of the sample and tip. This work provides guidance for implementing other NFOT techniques using radiation transmission and infrared emission .