MgO界面层对n-ZnO纳米棒/p-GaN异质结LED光电性能的影响  

Effect of MgO interface layer on photoelectric properties of n-ZnO nanorods/p-GaN heterojunction LED

作　　者：张忠俊[1] 张立春[1] 赵风周[1] 曲崇[1] 黄瑞志[1] 张敏[1] 李清山[1] 

机构地区：[1]鲁东大学物理与光电工程学院,山东烟台264025

出　　处：《光电子．激光》2014年第5期851-856,共6页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(11144010)资助项目

摘　　要：为了较好地实现n-ZnO的电致发光(EL),利用水热法在p-GaN外延片上制备了ZnO纳米棒阵列,构造了n-ZnO纳米棒/p-GaN异质结LED原型器件,并研究了MgO界面层对器件光电性能的影响。结果表明,n-ZnO纳米棒/p-GaN异质结器件具有明显的二极管整流效应。室温、正向偏压下,n-ZnO纳米棒/p-GaN异质结LED仅在430nm附近具有单一的发光峰,而n-ZnO纳米棒/MgO/p-GaN异质结LED的电致发光光谱由一个从近紫外到蓝绿光区的宽发光带组成。结合光致发光(PL)谱和Anderson能带模型,深入分析了n-ZnO纳米棒/p-GaN异质结的载流子复合机制。Limited by the technology conditions, carrier concentration and Hall mobility of p-GaN are low- er than those of n-ZnO. When the n-ZnO nanorods/p-GaN heterojunction device works under forward bias,the electrol （EL） mainly origins from p-GaN side. In order to realize electrolumines cence of n-ZnO,in this paper,heterojunction LEDs based on arrays of ZnO nanorods were fabricated on p-GaN films by hydrothermal method,and the effects of MgO interface layer on the photoelectric proper- ties of the device are studied. The results show that all the devices demonstrate nonlinear rectifying be- haviour. At room temperature, the EL spectra of the n-ZnO nanorods/p-GaN heterojunction diodes dis- play one emission peak centered at about 430 nm under forward bias. However,the EL spectra of n-ZnO nanorods/MgO/p-GaN heterostructure LED exhibit a broad emission band from near ultraviolet to blue- green region. Combining the photoluminescence （PL） spectrum and Anderson energy band diagram, the mechanisms of radiative recombination in n-ZnO nanorods/p-GaN heterojunction LEDs are discussed in detail.

关 键 词：n-ZnO纳米棒 P-GAN 异质结 电致发光(EL) 

分 类 号：O482.31[理学—固体物理]