Orientation-dependent band offsets between (AlxGa1−x)2O3 and Ga2O3
Orientation-dependent band offsets between (AlxGa1−x)2O3 and Ga2O3
复制标题
(AlxGa1−x)2O3 和 Ga2O3 之间与方向相关的能带偏移
DOI：
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发表时间：
2020
影响因子：
4
通讯作者：
C. D. Walle
中科院分区：
文献类型：
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作者：
Sai Mu;H. Peelaers;Yong;Mengen Wang;C. D. Walle
用密度泛函理论和杂化泛函方法研究了Al 2 O3和Ga 2 O3在四种不同取向[（100），（010），（001）和（2 <$01）]下的能带排列.通过与显式接口计算比较，我们确认，对齐可以可靠地提取板计算，原子弛豫和应变考虑。赝晶应变的存在使平均静电势以及能带边缘移动。Al 2 O3的拉伸应变会降低导带;绝对变形势计算为Al 2 O3为−9.5 eV，Ga 2 O3为−9.1 eV。我们的研究结果表明，最大的导带偏移将发生在具有（100）取向的赝晶（AlxGa 1 −x）2 O3/Ga 2 O3界面处，使我们能够估计调制掺杂场效应晶体管中二维电子气的密度。
Band alignments between Al2O3 and Ga2O3 are investigated for four different orientations [(100), (010), (001), and ( 2 ¯01)] using density functional theory with a hybrid functional. By comparing with explicit interface calculations, we confirm that alignments can be reliably extracted from slab calculations that take atomic relaxation and strain into account. The presence of pseudomorphic strain shifts the average electrostatic potential as well as the band edges. Tensile strain in Al2O3 is found to lower the conduction band; the absolute deformation potential is calculated to be −9.5 eV for Al2O3 and −9.1 eV for Ga2O3. Our results show that the largest conduction-band offset will occur at a pseudomorphic (AlxGa1−x)2O3/Ga2O3 interface with the (100) orientation, allowing us to estimate the density of the two-dimensional electron gas in a modulation-doped field-effect transistor.