Department of Mechanical Engineering
Kenneth E. Goodson
Lee, J., Bozorg-Grayeli, E., Kim, S., Asheghi, M., Wong, H.-S., and Goodson, K.E., 2013, "Phonon and Electron Transport through Ge2Sb2Te5 Films and Interfaces Bounded by Metals," Applied Physics Letters, Vol. 102, 191911.
While atomic vibrations dominate thermal conduction in the amorphous and face-centered cubic phases of Ge2Sb2Te5, electrons dominate in the hexagonal closed-packed (hcp) phase. Here we separate the electron and phonon contributions to the interface and volume thermal resistances for the three phases using time-domain thermoreflectance and electrical contact resistance measurements. Even when electrons dominate film-normal volume conduction (i.e. 70% for the hcp phase), their contribution to interface heat conduction is overwhelmed by phonons for high-quality interfaces with metallic TiN.