%A Quan-Jiang Lv(吕全江), Yi-Hong Zhang(张一鸿), Chang-Da Zheng(郑畅达), Jiang-Dong Gao(高江东), Jian-Li Zhang(张建立), Jun-Lin Liu(刘军林) %T Analysis of stress-induced inhomogeneous electroluminescence in GaN-based green LEDs grown on mesh-patterned Si (111) substrates with n-type AlGaN layer %0 Journal Article %D 2020 %J Chin. Phys. B %R 10.1088/1674-1056/ab96a2 %P 87801-087801 %V 29 %N 8 %U {https://cpb.iphy.ac.cn/CN/abstract/article_122730.shtml} %8 2020-08-05 %X Inhomogeneous electroluminescence (EL) of InGaN green LEDs grown on mesh-patterned Si (111) substrate had been investigated. Sample with n-AlGaN inserted between the pre-strained layers and the first quantum well showed the inhomogeneous EL in the low current density range. Near-field EL emission intensity distribution images depicted that inhomogeneity in the form of premature turn-on at the periphery of the LED chip, results in stronger emission intensity at the edges. This premature turn-on effect significantly reduces the luminous efficacy and higher ideality factor value due to locally current crowding effect. Raman measurement and fluorescence microscopy results indicated that the partially relaxed in-plane stress at the edge of the window region acts as a parasitic diode with a smaller energy band gap, which is a source of edge emission. Numerical simulations showd that the tilted triangular n-AlGaN functions like a forward-biased Schottky diode, which not only impedes carrier transport, but also contributes a certain ideality factor.