[13a-D419-1~12] 21.1 Joint Session K "Wide bandgap oxide semiconductor materials and devices"

[13a-D419-5] Dominant factors limiting carrier transport of ultra thin W-doped In₂O₃ films

〇Yutaka Furubayashi¹, Makoto Maehara², Toshiyuki Sakemi², Hisashi Kitami^1,2, Tetsuya Yamamoto¹ (1.Kochi Univ. Tech., 2.Sumitomo Heavy Industries, ltd.)

Keywords:Indium oxide, Ultrathin films, Electrical properties

In₂O₃ films has been mostly applied to transparent conducting films. However, its transport properties within ultrathin region have not fully investigated. In this study, we discussed the dependencies of the thickness and surface/interface roughness on its transport properties for ultrathin W-doped In₂O^₃ (IWO) films, in terms of classical size effects based on mean free path of carriers. These IWO films were grown by using reactive plasma deposition and were subsequently solid-state-crystallized. We found that diffuse scattering on its surface or interface became dominant at the thickness less than 20 nm. Moreover, we also found that the solid-state crystallization reduces the surface roughness and the corresponding diffuse scattering, which results in a high Hall mobility for these ultrathin IWO films.