title: Selective-Area MOCVD Growth and Carrier-Transport-Type Control of InAs(Sb)/GaSb Core-Shell Nanowires.
abstract: We report the first selective-area growth of high quality InAs(Sb)/GaSb core-shell nanowires on Si substrates using metal-organic chemical vapor deposition (MOCVD) without foreign catalysts. Transmission electron microscopy (TEM) analysis reveals that the overgrowth of the GaSb shell is highly uniform and coherent with the InAs(Sb) core without any misfit dislocations. To control the structural properties and reduce the planar defect density in the self-catalyzed InAs core nanowires, a trace amount of Sb was introduced during their growth. As the Sb content increases from 0 to 9.4%, the crystal structure of the nanowires changes from a mixed wurtzite (WZ)/zinc-blende (ZB) structure to a perfect ZB phase. Electrical measurements reveal that both the n-type InAsSb core and p-type GaSb shell can work as active carrier transport channels, and the transport type of core-shell nanowires can be tuned by the GaSb shell thickness and back-gate voltage. This study furthers our understanding of the Sb-induced crystal-phase control of nanowires. Furthermore, the high quality InAs(Sb)/GaSb core-shell nanowire arrays obtained here pave the foundation for the fabrication of the vertical nanowire-based devices on a large scale and for the study of fundamental quantum physics.
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, People's Republic of China.
authors.forename: Xianghai
authors.initials: X
authors.lastname: Ji
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, People's Republic of China.|College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Yang
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, People's Republic of China.
authors.forename: Wenna
authors.initials: W
authors.lastname: Du
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University , Beijing 100871, People's Republic of China.
authors.forename: Huayong
authors.initials: H
authors.lastname: Pan
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, People's Republic of China.|College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
keywords: Core−shell nanowires; InAs(Sb)/GaSb; crystal structure; electrical properties; metal−organic chemical vapor deposition; selective-area growth