Investigation of the thermal boundary resistance at the III-nitride/substrate interface using optical methods

J. Kuzmik , S. Bychikhin , D. Pogany , Christophe Gaquière (1) , E. Pichonat (2) , E. Morvan

1 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520
2 LASIRE - Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516

Heat removal from III-Nitride-based devices into a substrate depends also on an acoustic coupling at III-Nitride/substrate interface. We investigate thermal boundary resistance (TBR) and its effects on temperature distribution for GaN layers on Si, SiC, or sapphire substrates. Micro-Raman method is used for the investigation of TBR at the GaN/Si interface while the transient interferometric mapping (TIM) method is used for investigation of GaN/SiC and GaN/sapphire systems. Thermal modeling is used to analyze the experimental data. We found TBR to be ~7×10−8 m2 K/W for GaN/Si and ~1.2×10−7 m2 K/W for GaN/SiC interfaces. The role of TBR at the GaN/sapphire interface in the poor heat transfer from GaN to substrate is found to be less important. It is suggested that the substrate cooling efficiency may be improved if fewer defects are present at the interface to the GaN epistructure. ©2007 American Institute of Physics

Domaines: Sciences de l'ingénieur [physics]

J. Kuzmik, S. Bychikhin, D. Pogany, Christophe Gaquière, E. Pichonat, et al.. Investigation of the thermal boundary resistance at the III-nitride/substrate interface using optical methods. Journal of Applied Physics, 2007, 101, pp.054508-1-6. ⟨10.1063/1.2435799⟩. ⟨hal-00283973⟩