[15a-S4_202-1~8] 9.3 Nanoelectronics

10:30 AM - 10:45 AM JST(1:30 AM - 1:45 AM UTC)English Presentation

[15a-S4_202-5] Thickness-Dependent Band Structure of In₂O₃ and Ga-Doped In₂O₃ Nanosheets: A First-Principles Study

〇(P)Chitra Pandy¹, Masaharu Kobayashi¹ (1.Institute of Industrial Science, The University of Tokyo)

Keywords:

Oxide Semicondcutors,Ga Doped In2O3,Density Functional Theory Calculations,Band Structure,Density of States

In₂O₃-based oxide semiconductors are promising channel materials for monolithic three-dimensional (M3D) integration owing to their high electron mobility, wide bandgap, and compatibility with low-temperature back-end-of-line processes. As channel thickness is scaled below 5 nm, quantum confinement plays a critical role in determining the electronic structure. In this work, first-principles density functional theory calculations are used to investigate the thickness-dependent electronic properties of pristine In₂O₃ and Ga-doped In₂O₃ ultrathin slabs with thicknesses ranging from 1 to 5 nm. The bandgap of both systems increases with decreasing thickness due to quantum confinement, observed as an upward shift of the conduction band minimum. At all thicknesses, Ga-doped In₂O₃ exhibits a systematically larger bandgap than pristine In₂O₃. Projected density-of-states analysis shows that Ga incorporation enhances cation–oxygen hybridization, leading to a downward shift of the valence band maximum and a slight modification of the conduction band. These results indicate the role of thickness confinement and Ga incorporation in determining the electronic structure of ultrathin In₂O₃-based oxide semiconductors.