The electrical conductivity of cubic (In$_{1-x}$Ga$_x$)$_2$O$_3$ films ($x\le0.18$): Native point defects, Sn-doping, and the surface electron accumulation layer

Alexandra Papadogianni; Takahiro Nagata; Oliver Bierwagen

doi:10.35848/1347-4065/ac4ec7

paper

The electrical conductivity of cubic (In $_{1 - x}$ Ga $_{x}$ ) $_{2}$ O $_{3}$ films ( $x \leq 0.18$ ): Native point defects, Sn-doping, and the surface electron accumulation layer

arXiv:2109.12875 · doi:10.35848/1347-4065/ac4ec7

Abstract

The alloying of the group-III transparent semiconducting sesquioxides In $_{2}$ O $_{3}$ and Ga $_{2}$ O $_{3}$ can lead to a modulation of the properties of the parent compounds, e.g., the shallow- and deep-donor character of the oxygen vacancy or the presence and absence of a surface electron accumulation layer, respectively. In this work, we investigate the effect of alloying on the electron transport properties of unintentionally-doped single-crystalline and textured bixbyite (In $_{1 - x}$ Ga $_{x}$ ) $_{2}$ O $_{3}$ thin films annealed in oxygen and vacuum with Ga contents up to $x$ =0.18. Hall effect measurements demonstrate a surprising increase in electron density due to native defects with added Ga. This increase may be related to the incorporation of Ga-interstitials or oxygen vacancies induced by Ga-related unit-cell distortions. A combined investigation based on hard and soft x-ray photoelectron spectroscopy measurements demonstrates the existence of the surface electron accumulation layer for all alloy films and, hence, no depletion up to $x$ =0.18. Finally, we additionally demonstrate a single-crystalline (In $_{0.92}$ Ga $_{0.08}$ ) $_{2}$ O $_{3}$ :Sn film, as a possible transparent conductive oxide with a wider band gap than that of (Sn-doped) In $_{2}$ O $_{3}$ .

7 pages, 4 figures

References in corpus (3)

Cited by in corpus (1)

Molecular beam epitaxy of single-crystalline bixbyite (In $_{1 - x}$ Ga $_{x}$ ) $_{2}$ O $_{3}$ films ( $x \leq 0.18$ ): Structural properties and consequences of compositional inhomogeneity

The electrical conductivity of cubic (In1−x​Gax​)2​O3​ films (x≤0.18): Native point defects, Sn-doping, and the surface electron accumulation layer

Abstract

References in corpus (3)

Cited by in corpus (1)

The electrical conductivity of cubic (In $_{1 - x}$ Ga $_{x}$ ) $_{2}$ O $_{3}$ films ( $x \leq 0.18$ ): Native point defects, Sn-doping, and the surface electron accumulation layer