title: Large-scale horizontally aligned ZnO microrod arrays with controlled orientation, periodic distribution as building blocks for chip-in piezo-phototronic LEDs.
abstract: A novel method of fabricating large-scale horizontally aligned ZnO microrod arrays with controlled orientation and periodic distribution via combing technology is introduced. Horizontally aligned ZnO microrod arrays with uniform orientation and periodic distribution can be realized based on the conventional bottom-up method prepared vertically aligned ZnO microrod matrix via the combing method. When the combing parameters are changed, the orientation of horizontally aligned ZnO microrod arrays can be adjusted (θ = 90° or 45°) in a plane and a misalignment angle of the microrods (0.3° to 2.3°) with low-growth density can be obtained. To explore the potential applications based on the vertically and horizontally aligned ZnO microrods on p-GaN layer, piezo-phototronic devices such as heterojunction LEDs are built. Electroluminescence (EL) emission patterns can be adjusted for the vertically and horizontally aligned ZnO microrods/p-GaN heterojunction LEDs by applying forward bias. Moreover, the emission color from UV-blue to yellow-green can be tuned by investigating the piezoelectric properties of the materials. The EL emission mechanisms of the LEDs are discussed in terms of band diagrams of the heterojunctions and carrier recombination processes.
authors.affiliation: Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, No.88-Keling Road, Suzhou New District, 215163, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Guo
authors.forename: Haiwen
authors.initials: H
authors.lastname: Li
authors.forename: Lianqun
authors.initials: L
authors.lastname: Zhou
authors.forename: Dongxu
authors.initials: D
authors.lastname: Zhao
authors.forename: Yihui
authors.initials: Y
authors.lastname: Wu
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Chuanyu
authors.initials: C
authors.lastname: Li
authors.forename: Jia
authors.initials: J
authors.lastname: Yao
keywords: aligned ZnO microrods; arrays; building blocks; chip-in light emitting diodes; controlled orientation; transformations