title: Position-controlled AlN/ZnO coaxial nanotube heterostructure arrays for electron emitter applications.
abstract: We studied the fabrication and field-emission characteristics of position-controlled AlN/ZnO nanotube heterostructure arrays. AlN layers with various thicknesses from 20 to 52 nm were deposited coaxially on the position-controlled ZnO nanotube arrays. The field-emission properties of the coaxial AlN/ZnO nanotube arrays were controlled using the AlN thickness and the nanotube interdistance. As compared to the bare ZnO nanotube arrays, the AlN-coated coaxial nanotube arrays exhibited enhanced electron emission, and the optimum AlN coating layer thickness on the nanotube tips was 26 nm. The improved field emission from the coaxial nanotube heterostructures is attributed to the low electron affinity and the thickness modulation effect of the AlN coating layer.
authors.affiliation: National Creative Research Initiative Center for Semiconductor Nanorods and Department of Materials Science and Engineering, POSTECH, Pohang, Gyeongbuk 790-784, Korea.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Kim
authors.forename: Jeonghui
authors.initials: J
authors.lastname: Cho
authors.forename: Young Joon
authors.initials: YJ
authors.lastname: Hong
authors.forename: Jong-Myeong
authors.initials: JM
authors.lastname: Jeon
authors.forename: Miyoung
authors.initials: M
authors.lastname: Kim
authors.forename: Chunli
authors.initials: C
authors.lastname: Liu
authors.forename: Gyu-Chul
authors.initials: GC
authors.lastname: Yi