Thermal conductivity measurement of diamond and β-Ga2O3 thin films by a 3ω method

Ga
₂
O
₃
, is one of the promising candidates as wide bandgap material, having potential advantage over SiC and GaN. The low thermal conductivity of Ga
₂
O
₃
is a major drawback, however, there are not much reports for thermal conductivity measurement for Ga
₂
O
₃
thin films. In this study, the thermal conductivity of a single-crystal and polycrystalline diamond and a single-crystal β-Ga
₂
O
₃
[-201] free-standing substrate was evaluated by the 3ω method. 23.3, 1810, and 1380 W/m-K, were obtained as thermal conductivity of β-Ga
₂
O
₃
[-201], Ila-type single crystal diamond, and polycrystalline diamond, respectively.