We investigated the thermal conductivity of 200-nm-thick amorphous indium-gallium-zinc-oxide (a-IGZO) films. Films with a chemical composition of In : Ga : Zn = 1 : 1 : 0:6 were prepared by dc magnetron sputtering using an IGZO ceramic target and an Ar-O2 sputtering gas. The carrier density of the films was systematically controlled from 1014 to > 10 19 cm-3 by varying the O2 flow ratio. Their Hall mobility was slightly higher than 10 cm2.V-1.s -1. Those films were sandwiched between 100-nm-thick Mo layers; their thermal diffusivity, measured by a pulsed light heating thermoreflectance technique, was ∼5.4 × 10-7 m2.s-1 and was almost independent of the carrier density. The average thermal conductivity was 1.4W.m-1.K-1.
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