Intrinsic electron mobility limits in β -Ga2O3

作者：Nan Ma, Nicholas Tanen, Amit Verma, Zhi Guo, Tengfei Luo, Huili (Grace) Xing, Debdeep Jena · 发表于：Applied Physics Letters · 年份：2016 · DOI：10.1063/1.4968550 · 被引用次数：425 · 研究领域：Ga2O3 and related materials、GaN-based semiconductor devices and materials、Thin-Film Transistor Technologies

By systematically comparing experimental and theoretical transport properties, we identify the polar optical phonon scattering as the dominant mechanism limiting electron mobility in β–Ga2O3 to <200 cm2/V s at 300 K for donor doping densities lower than ∼1018 cm–3. Despite similar electron effective mass of β–Ga2O3 to GaN, the electron mobility is ∼10× lower because of a massive Fröhlich interaction, due to the low phonon energies stemming from the crystal structure and strong bond ionicity. Based on the theoretical and experimental analysis, we provide an empirical expression for electron mobility in β–Ga2O3 that should help calibrate its potential in high performance device design and applications.