title: Crystal Phase- and Orientation-Dependent Electrical Transport Properties of InAs Nanowires.
abstract: We report a systematic study on the correlation of the electrical transport properties with the crystal phase and orientation of single-crystal InAs nanowires (NWs) grown by molecular-beam epitaxy. A new method is developed to allow the same InAs NW to be used for both the electrical measurements and transmission electron microscopy characterization. We find both the crystal phase, wurtzite (WZ) or zinc-blende (ZB), and the orientation of the InAs NWs remarkably affect the electronic properties of the field-effect transistors based on these NWs, such as the threshold voltage (VT), ON-OFF ratio, subthreshold swing (SS) and effective barrier height at the off-state (ΦOFF). The SS increases while VT, ON-OFF ratio, and ΦOFF decrease one by one in the sequence of WZ ⟨0001⟩, ZB ⟨131⟩, ZB ⟨332⟩, ZB ⟨121⟩, and ZB ⟨011⟩. The WZ InAs NWs have obvious smaller field-effect mobility, conductivities, and electron concentration at VBG = 0 V than the ZB InAs NWs, while these parameters are not sensitive to the orientation of the ZB InAs NWs. We also find the diameter ranging from 12 to 33 nm shows much less effect than the crystal phase and orientation on the electrical transport properties of the InAs NWs. The good ohmic contact between InAs NWs and metal remains regardless of the variation of the crystal phase and orientation through temperature-dependent measurements. Our work deepens the understanding of the structure-dependent electrical transport properties of InAs NWs and provides a potential way to tailor the device properties by controlling the crystal phase and orientation of the NWs.
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, China.
authors.forename: Mengqi
authors.initials: M
authors.lastname: Fu
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Tang
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, China.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Ning
authors.affiliation: State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, China.
authors.forename: Xianlong
authors.initials: X
authors.lastname: Wei
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen
keywords: InAs nanowires; crystal orientation; crystal phase; electrical properties; nanomanipulation