title: Nanointerlayer induced electroluminescence transition from ultraviolet- to red-dominant mode for n-Mn:ZnO/N-GaN heterojunction.
abstract: High-quality Mn:ZnO (MZO) film had been prepared on N-GaN coated sapphire substrates followed by postdeposition thermal annealing treatment at 700 °C. For the annealed MZO/GaN heterojunction, a 15 nm cubic structural ZnGa(2)O(4) layer was observed at the MZO/GaN interface through transmission electron microscope analysis. Through electroluminescence (EL) measurement, the formation of the nanointerface results in an EL transition from ultraviolet- to red-dominant mode for n-Mn:ZnO/N-GaN heterojunction light-emitting diodes (LEDs). The heterojunction LED showed a rectification ratio of ∼2.0 × 10(5) at ±2 V, a dark current of 3.5 nA at -2 V and a quite strong red EL with a low turn-on voltage of 3 V. On the basis of the energy band diagram, we think the EL transition from ultraviolet- to red-dominant mode is mainly due to the formation of a thin oxide blocking nanolayer at the MZO/GaN interface during the annealing process.
authors.affiliation: Department of Electronic Science and Technology and Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, People's Republic of China.
authors.forename: Hai
authors.initials: H
authors.lastname: Zhou
authors.forename: Guojia
authors.initials: G
authors.lastname: Fang
authors.forename: Qike
authors.initials: Q
authors.lastname: Jiang
authors.forename: Yongdan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Nishuang
authors.initials: N
authors.lastname: Liu
authors.forename: Xiao
authors.initials: X
authors.lastname: Zou
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Mo
authors.forename: Yihe
authors.initials: Y
authors.lastname: Liu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Wang
authors.forename: Xianquan
authors.initials: X
authors.lastname: Meng
authors.forename: Xingzhong
authors.initials: X
authors.lastname: Zhao