title: Thermal measurement. Nanoscale temperature mapping in operating microelectronic devices.
abstract: Modern microelectronic devices have nanoscale features that dissipate power nonuniformly, but fundamental physical limits frustrate efforts to detect the resulting temperature gradients. Contact thermometers disturb the temperature of a small system, while radiation thermometers struggle to beat the diffraction limit. Exploiting the same physics as Fahrenheit's glass-bulb thermometer, we mapped the thermal expansion of Joule-heated, 80-nanometer-thick aluminum wires by precisely measuring changes in density. With a scanning transmission electron microscope and electron energy loss spectroscopy, we quantified the local density via the energy of aluminum's bulk plasmon. Rescaling density to temperature yields maps with a statistical precision of 3 kelvin/hertz(-1/2), an accuracy of 10%, and nanometer-scale resolution. Many common metals and semiconductors have sufficiently sharp plasmon resonances to serve as their own thermometers.
authors: Center for Electron Microscopy and Microanalysis, University of Southern California, Los Angeles, CA 90089, USA. matthew.mecklenburg@usc.edu regan@physics.ucla.edu.
authors: Matthew
authors: M
authors: Mecklenburg
authors: Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA. California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA.
authors: William A
authors: WA
authors: Hubbard
authors: Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA. California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA.
authors: E R
authors: ER
authors: White
authors: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
authors: Rohan
authors: R
authors: Dhall
authors: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
authors: Stephen B
authors: SB
authors: Cronin
authors: Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
authors: Shaul
authors: S
authors: Aloni
authors: Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA. California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA. matthew.mecklenburg@usc.edu regan@physics.ucla.edu.
authors: B C
authors: BC
authors: Regan