Electron Thermal Microscopy

Abstract

We present real-time, nanoscale temperature mapping using a transmission electron microscope and standard phase transitions in metal islands. Islands are deposited on the reverse side of commercially available silicon nitride membranes, while local thermal gradients are produced by Joule heating in a thin wire on the front side of the membrane. Change in contrast due to the liquid-solid transition in the islands allows the mapping of absolute temperature, as above or below the transition temperature, over the entire field-of-view. Experiments demonstrate nanoscale (<100 nm) resolution and video-rate (>30 thermal-images per second) speed, supported by combined electrical and thermal modeling. This provides a generic and adaptable platform for nanoscale thermal characterization independent of strong probe coupling and optical effects.

Controlling the thermal contact resistance of a carbon nanotube heat spreader

“…In this relationship V is the electric potential, and , is the electrical conductivity, with the value at room temperature and the temperature coefficient, both characterized previously. 25 In the modeling, steady state conditions were assumed. Since Finally, values are converted to one-dimensional R c values reported in the text by dividing by the width of the nanotube in the finite element model.…”

“…23,24 To perform these studies, we employ electron thermal microscopy (EThM) described elsewhere. 25 In EThM, thermal images are obtained by transmission electron microscope (TEM) observations of the in-situ solid to liquid phase transition of low-melting-point (156.6 °C) nanoscale indium (In) islands, acting as binary thermometers, evaporated on the back of electron transparent silicon nitride (SiN x ) substrates. 26 In the present study, measurements are done on two types of samples.…”

Thermometry at the nanoscale

“…Brintlinger et al 247 have reported a method for mapping temperature at the nanoscale using a transmission electron microscope and the melting point of metal islands. The germanium metal islands are deposited on the reverse side of a commercial silicon nitride membrane whereas local temperature gradients are produced by Joule heating in a thin wire in the front side of the membrane.…”

Vanadium dioxide nanowire-based microthermometer for quantitative evaluation of electron beam heating

“…To date, robust solutions for quantitative measurement of local temperature and heat flow at nanoscale dimensions are very limited [1][2][3][4][5][6][7][8] . In particular, inhomogeneous temperature distributions at these size scales are not easily probed with typical small-scale thermal measurements such as infrared thermometers or scanning thermal microscopy 2,8 .…”

“…Experimentally, scanning thermal microscopy 2 requires a complicated setup, which is difficult to combine with TEM. The melting point of a material can be used to quantify temperature, but this is typically only a single-point or singletemperature detection [4][5][6][7] , especially when trying to measure the temperature of individual small particles. As environmental interactions become more accessible through modern in situ TEM instrumentation, it is essential to distinguish temperature effects from other electron beam effects 11,12 .…”