Atomic-layer-deposited Al2O3 on Bi2Te3 for topological insulator field-effect transistors

作者：Han Liu, Peide D. Ye · 发表于：Applied Physics Letters · 年份：2011 · DOI：10.1063/1.3622306 · 被引用次数：40 · 研究领域：Topological Materials and Phenomena、Graphene research and applications、2D Materials and Applications

We report dual-gate modulation of topological insulator field-effect transistors (TI FETs) made on Bi2Te3 thin flakes with integration of atomic-layer-deposited (ALD) Al2O3 high-k dielectric. Atomic force microscopy study shows that ALD Al2O3 is uniformly grown on this layer-structured channel material. Electrical characterization reveals that the right selection of ALD precursors and the related surface chemistry play a critical role in device performance of Bi2Te3 based TI FETs. We realize both top-gate and bottom-gate control on these devices, and the highest modulation rate of 76.1% is achieved by using simultaneous dual gate control.