Anisotropic thermal conductivity in single crystal β-gallium oxide

• DOI: 10.1063/1.4916078
• Publication Date: 2015-03-19T17:00:38Z
• Authors: Zhi Guo; Amit Verma; Xufei Wu; Fangyuan Sun; Austin Hickman; Takekazu Masui; Akito Kuramata; Masataka Higashiwaki; Debdeep Jena; Tengfei Luo
• Keywords: Crystal (programming language); Atmospheric temperature range; Phonon scattering

The thermal conductivities of beta-Ga2O3 single crystals along four different crystal directions were measured in the temperature range 80-495K using time domain thermoreflectance (TDTR) method. A large anisotropy was found. At room temperature, [010] direction has highest conductivity 27.0+/-2.0 W/mK, while that [100] lowest value 10.9+/-1.0 W/mK. high temperatures, follows a ~1/T relationship characteristic Umklapp phonon scattering, indicating phonon-dominated heat transport \b{eta}-Ga2O3 crystal. experimental is supported by first-principles calculations which suggest due to differences speed sound directions.