title: Emission color-tuned light-emitting diode microarrays of nonpolar In(x)Ga(1-x)N/GaN multishell nanotube heterostructures.
abstract: Integration of nanostructure lighting source arrays with well-defined emission wavelengths is of great importance for optoelectronic integrated monolithic circuitry. We report on the fabrication and optical properties of GaN-based p-n junction multishell nanotube microarrays with composition-modulated nonpolar m-plane InxGa1-xN/GaN multiple quantum wells (MQWs) integrated on c-sapphire or Si substrates. The emission wavelengths were controlled in the visible spectral range of green to violet by varying the indium mole fraction of the InxGa1-xN MQWs in the range 0.13 ≤ x ≤ 0.36. Homogeneous emission from the entire area of the nanotube LED arrays was achieved via the formation of MQWs with uniform QW widths and composition by heteroepitaxy on the well-ordered nanotube arrays. Importantly, the wavelength-invariant electroluminescence emission was observed above a turn-on of 3.0 V because both the quantum-confinement Stark effect and band filling were suppressed due to the lack of spontaneous inherent electric field in the m-plane nanotube nonpolar MQWs. The method of fabricating the multishell nanotube LED microarrays with controlled emission colors has potential applications in monolithic nonpolar photonic and optoelectronic devices on commonly used c-sapphire and Si substrates.
authors.affiliation: Faculty of Nanotechnology &Advanced Materials Engineering, Graphene Research Institute, and Hybrid Materials Research Center, Sejong University, Seoul 143-747, Korea.
authors.forename: Young Joon
authors.initials: YJ
authors.lastname: Hong
authors.affiliation: KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701, Korea.
authors.forename: Chul-Ho
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States.
authors.forename: Jinkyoung
authors.initials: J
authors.lastname: Yoo
authors.affiliation: Department of Physics &Astronomy and Institute of Applied Physics, Seoul National University, Seoul 151-747, Korea.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Faculty of Nanotechnology &Advanced Materials Engineering, Graphene Research Institute, and Hybrid Materials Research Center, Sejong University, Seoul 143-747, Korea.
authors.forename: Junseok
authors.initials: J
authors.lastname: Jeong
authors.affiliation: Department of Materials Science and Engineering, Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 151-744, Korea.
authors.forename: Miyoung
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Physics &Astronomy and Institute of Applied Physics, Seoul National University, Seoul 151-747, Korea.
authors.forename: Gyu-Chul
authors.initials: GC
authors.lastname: Yi