Temperature-Dependent Thermal Boundary Conductance at Al/Al2O3 and Pt/Al2O3 interfaces

Abstract

With the ever-decreasing size of microelectronic devices, growing applications of superlattices, and development of nanotechnology, thermal resistances of interfaces are becoming increasingly central to thermal management. Although there has been much success in understanding thermal boundary conductance at low temperatures, the current models applied at temperatures more common in device operation are not adequate due to our current limited understanding of phonon transport channels. In this study, the scattering processes in Al and Pt films on Al 2 O 3 substrates are examined by transient thermoreflectance testing at high temperatures. At high temperatures, traditional models predict the thermal boundary conductance to be relatively constant in these systems due to assumptions about phonon elastic scattering. Experiments, however, show an increase in the conductance indicating potential inelastic phonon processes.

Thermal Boundary Conductance: A Materials Science Perspective

“…The TBC between Al and clean sapphire has been measured by a number of investigators (36,37,128), with good convergence around h = 185 ± 15 MW/(m 2 ·K) at 300 K. This system is particularly suitable for benchmarking because sapphire is commercially available with very low surface roughness, is easily cleaned by baking in air at high T, and does not react with Al.…”

Thermal boundary conductance of transition metals on diamond

“…In this paper, the link between adhesion of a metallic layer on diamond and TBC between the former and the latter is emphasized. TDTR has long been used successfully to measure the TBC of interfaces in metal/metal (Clemens et al, 1988;Gundrum et al, 2005) or metal/dielectric systems (Hopkins et al, 2007;Hopkins et al 2008;Lyeo and Cahill 2006;Stevens et al, 2005;Stoner and Maris 1993). This technique has the advantage to offer insight on nanometer-scale thermal diffusion effects, and thus is able to isolate the in uence of a single interface on conductivity (Cahill et al, 2002.…”

Thermal boundary conductance across metal-nonmetal interfaces: effects of electron-phonon coupling both in metal and at interface

“…The investigation on the TBC across metal-nonmetal interfaces, which is the total heat current Q divided by the temperature drop at the interface shown in Figure 1(a), is one of the most important topics for thermal engineering. Experimentally, the TBC across metal-nonmetal interfaces is measured with the thermoreflectance technique [3][4][5][6][7] and the steady state technique [8]. One of the concerns to researchers is that some experimentally measured values significantly deviate from the theoretical calculated ones [9,10] where only phonons are considered.…”