Absorption of light in InP nanowire arrays

作     者：Nicklas Anttu Alireza Abrand Damir Asoli Magnus Heurlin Ingvar Aberg Lars Samuelson Magnus Borgstrom 

作者机构：Division of Solid State Physics and the Nanometer Structure Consortium at Lund University (nmC@LU) Lund University Box 118 Lund 22100 Sweden Sol Voltaics AB Ideon Science Park Scheelevagen 17 Lund 22370 Sweden 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2014年第7卷第6期

页      面：816-823页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0702[理学-物理学] 

基　　金：supported by the Swedish Research Council (VR) the Swedish Foundation for Strategic Research (SSF) the Swedish Energy Agency the Nanometer Structure Consortium at Lund University (nmC@LU) the Nordic Innovation program NANORDSUN the Knut and Alice Wallenberg Foundation 

主　　题：indium phosphide semiconductor nanowire absorption of light 

摘      要：An understanding of the absorption of light is essential for efficient photovoltaic and photodetection applications with III-V nanowire arrays. Here, we correlate experiments with modeling and verify experimentally the predicted absorption of light in InP nanowire arrays for varying nanowire diameter and length. We find that 2,000 nm long nanowires in a pitch of 400 nm can absorb 94% of the incident light with energy above the band gap and, as a consequence, light which in a simple ray-optics description would be travelling between the nanowires can be efficiently absorbed by the nanowires. Our measurements demonstrate that the absorption for long nanowires is limited by insertion reflection losses when light is coupled from the air top-region into the array. These reflection losses can be reduced by introducing a smaller diameter to the nanowire-part closest to the air top-region. For nanowire arrays with such a nanowire morphology modulation, we find that the absorptance increases monotonously with increasing diameter of the rest of the nanowire.