Zhang Lichun, Li Qingshan, Shang Liang, Wang Feifei, Qu Chong, Zhao Fengzhou
School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China.
Opt Express. 2013 Jul 15;21(14):16578-83. doi: 10.1364/OE.21.016578.
n-ZnO/p-GaN heterojunction light emitting diodes with different interfacial layers were fabricated by pulsed laser deposition. The electroluminescence (EL) spectra of the n-ZnO/p-GaN diodes display a broad blue-violet emission centered at 430 nm, whereas the n-ZnO/ZnS/p-GaN and n-ZnO/AlN/p-GaN devices exhibit ultraviolet (UV) emission. Compared with the AlN interlayer, which is blocking both electron and hole at hetero-interface, the utilization of ZnS as intermediate layer can lower the barrier height for holes and keep an effective blocking for electron. Thus, an improved UV EL intensity and a low turn-on voltage (~5V) were obtained. The results were studied by peak-deconvolution with Gaussian functions and were discussed using the band diagram of heterojunctions.
采用脉冲激光沉积法制备了具有不同界面层的n-ZnO/p-GaN异质结发光二极管。n-ZnO/p-GaN二极管的电致发光（EL）光谱显示出以430nm为中心的宽蓝紫色发射，而n-ZnO/ZnS/p-GaN和n-ZnO/AlN/p-GaN器件则呈现紫外（UV）发射。与在异质界面处同时阻挡电子和空穴的AlN中间层相比，使用ZnS作为中间层可以降低空穴的势垒高度，并对电子保持有效的阻挡。因此，获得了改善的紫外EL强度和较低的开启电压（~5V）。通过用高斯函数进行峰去卷积研究了结果，并使用异质结的能带图进行了讨论。
