title: Simulation and Experimental Study on Anti-reflection Characteristics of Nano-patterned Si Structures for Si Quantum Dot-Based Light-Emitting Devices.
abstract: Surface-textured structure is currently an interesting topic since it can efficiently reduce the optical losses in advanced optoelectronic devices via light management. In this work, we built a model in finite-difference time-domain (FDTD) solutions by setting the simulation parameters based on the morphology of the Si nanostructures and compared with the experimental results in order to study the anti-reflection behaviors of the present nano-patterned structures. It is found that the reflectance is gradually reduced by increasing the depth of Si nanostructures which is in well agreement with the experimental observations. The reflectance can be lower than 10 % in the light range from 400 to 850 nm for Si nano-patterned structures with a depth of 150 nm despite the quite low aspect ratio, which can be understood as the formation of gradually changed index layer and the scattering effect of Si nano-patterned structures. By depositing the Si quantum dots/SiO2 multilayers on nano-patterned Si substrate, the reflectance can be further suppressed and the luminescence intensity centered at 820 nm from Si quantum dots is enhanced by 6.6-fold compared with that of flat one, which can be attributed to the improved light extraction efficiency. However, the further etch time causes the reduction of luminescence intensity from Si quantum dots which may ascribe to the serious surface recombination of carriers.
authors.affiliation: National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
authors.forename: Wenyi
authors.initials: W
authors.lastname: Shao
authors.affiliation: National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Lu
authors.affiliation: National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. junxu@nju.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.affiliation: National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Xu
authors.affiliation: National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
authors.forename: Kunji
authors.initials: K
authors.lastname: Chen
keywords: Anti-reflection; Photoluminescence; Si nano-patterned structures