On the upper limit of thermal conductivity GaN crystals

• Published in: Solid state communications 2007-10, Vol.144 (3), p.114-117
• Main Authors: Danilchenko, B.A., Obukhov, I.A., Paszkiewicz, T., Wolski, S., Jeżowski, A.
• Format: Article
• Language: English
• Subjects: A. Semiconductors; C. Point defects; Condensed matter: structure, mechanical and thermal properties; D. Heat conduction; Exact sciences and technology; Nonelectronic thermal conduction and heat-pulse propagation in solids; thermal waves; Physics; Transport properties of condensed matter (nonelectronic)
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2007.08.007

The maximal value of thermal conductivity κ max of the perfect wurtzite GaN crystal containing isotopes of natural abundance is estimated. Our upper limit of κ = 4800 W/K m at T max = 32 K is smaller than that calculated by Liu and Balandin κ = 6000 W/K m and higher than that obtained by Slack et al. κ = 3750 W/K m . The phenomenological dependence κ ∝ T − 1.43 obtained by Mion et al. for the temperature interval 300–450 K is extended to 200–300 K. For temperatures higher than T max the best fitting of our experimental data to Callaway’s formula is obtained for Grueneisen’s constant equal to γ = 1.35 .