The Thermal Conductivity Tensor of β‐Ga<sub>2</sub>O<sub>3</sub> from 300 to 1275 K
Detlef Klimm, Binderiya Amgalan, Steffen Ganschow, Albert Kwasniewski, Zbigniew Galazka, Matthias Bickermann
Abstract
Abstract Laser‐flash measurements of the thermal conductivity of Czochralski‐grown β‐Ga 2 O 3 single crystals are reported perpendicular to four independent crystallographic lattice planes , (010), (001), and (100) between room temperature and 1200 K. λ is represented by a symmetric tensor of rank 2 and has four independent components. Tensor components W m −1 K −1 and W m −1 K −1 (values for 300 K) can be directly measured. W m −1 K −1 and W m −1 K −1 , instead, are obtained by combining W m −1 K and W m −1 K. The crystallographic ‐axis is the direction with the highest thermal conductivity, λ 22 . The thermal conductivity assumes its lowest value (11.73 W m −1 K −1 ) in a direction close to the crystallographic ‐axis. However, this direction does not coincide with , and changes with temperature.