| About this Abstract |
| Meeting |
2011 Electronic Materials Conference
|
| Symposium
|
2011 Electronic Materials Conference
|
| Presentation Title |
R5, Effect of Dislocation Density on Thermal Boundary Conductance across GaSb/GaAs Interfaces |
| Author(s) |
Patrick E. Hopkins, John Duda, Leslie Phinney, Stephen Clark, Christopher Hains, Thomas Rotter, Ganesh Balakrishnan |
| On-Site Speaker (Planned) |
Patrick E. Hopkins |
| Abstract Scope |
Thermal transport across solid interfaces, which is a major inhibitor of heat flow in nanosystems, is quantified by the thermal boundary conductance, h. A greater understanding of h at III-V interfaces can lead to mitigation and control of heat transfer in optoelectronic structures, thereby furthering device engineering and development. In this work, we measure h across GaSb/GaAs interfaces with time-domain thermoreflectance (TDTR). We grow GaSb films on GaAs substrates via two different epitaxial techniques leading to different dislocation densities around the GaSb/GaAs boundary. In addition, these different growth techniques cause the dislocation densities of the GaSb films to vary, thus changing the surface morphology of the films. Therefore, we also study the effect of dislocation density and interface roughness on h at Al/GaSb interfaces, as a thin 100 nm Al film is deposited on the GaSb surface for TDTR measurements. Our measurements indicate that dislocations around the GaSb interface cause a large reduction in h. We quantify the phonon scattering with a variation of the diffuse mismatch model (DMM) in which phonon propagation and scattering parallels photon attenuation. Our model fits the measured data well, and the resulting phonon attenuation coefficients are independent of dislocation density. This indicates that attenuating phonon scattering events around GaSb interfaces are intrinsic to the materials comprising the interface. These thermal results have implications for the design, growth, and selection of materials in laser diodes and other gallium-based optoelectronics. P.E.H. is appreciative for funding from the LDRD program office through the Sandia National Laboratories Harry S. Truman Fellowship Program. J.C.D. is appreciative for funding from the National Science Foundation Graduate Research Fellowship Program and the Student Intern Program at Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the United States Department of Energy’s National Nuclear Security Administration under Contract DE-AC04-94AL85000. |
| Proceedings Inclusion? |
Undecided |