当前位置: X-MOL 学术J. Nanophotonics › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Light extraction efficiency of AlGaN nanowire deep ultraviolet light-emitting diodes on Si with different photonic structures
Journal of Nanophotonics ( IF 1.5 ) Pub Date : 2021-07-01 , DOI: 10.1117/1.jnp.15.036002
Jiaying Lu 1 , Mohammad Fazel Vafadar 1 , Songrui Zhao 1
Affiliation  

The low light extraction efficiency (LEE) stemming from the transverse-magnetic dominant emission is one of the major factors limiting the performance of aluminum gallium nitride (AlGaN)-based deep ultraviolet (UV) light-emitting diodes (LEDs) when the light emission wavelengths are close to 200 nm. These wavelengths, nonetheless, are pivotal to applications including sensing and sterilization and are considered human safe. We investigate the LEE of AlGaN/AlN nanowire (NW) deep UV LEDs emitting at 225 nm, with a focus on the top-surface LEE by considering different NW arrangements, typical NW spacings and radii from AlGaN NWs grown by selective area epitaxy, the influence of Si on the LEE in comparison to an Al reflector, and graphene as the top electrode. Our results show that given the selected range of design parameters, the top-surface LEE for honeycomb, square, and hexagonal lattices can be up to around 42% for complete devices on Si with the graphene top electrode; and compared to using an Al reflector, the Si substrate does not reduce LEE considerably. In the end, the light extraction mechanism is discussed by simulating the two-dimensional photonic crystal band structures.

中文翻译:

不同光子结构的Si上AlGaN纳米线深紫外发光二极管的光提取效率

源于横向磁主导发射的低光提取效率 (LEE) 是限制基于氮化铝镓 (AlGaN) 的深紫外 (UV) 发光二极管 (LED) 性能的主要因素之一。波长接近 200 nm。尽管如此,这些波长对于包括传感和灭菌在内的应用至关重要,并且被认为是对人体安全的。我们研究了发射 225 nm 的 AlGaN/AlN 纳米线 (NW) 深 UV LED 的 LEE,通过考虑不同的 NW 排列、典型的 NW 间距和通过选择性区域外延生长的 AlGaN NW 的半径,重点关注顶面 LEE,与铝反射器和石墨烯作为顶部电极相比,Si 对 LEE 的影响。我们的结果表明,给定设计参数的选定范围,对于带有石墨烯顶部电极的 Si 上的完整器件,蜂窝、方形和六边形晶格的顶面 LEE 可高达约 42%;与使用 Al 反射器相比,Si 衬底不会显着降低 LEE。最后,通过模拟二维光子晶体能带结构讨论了光提取机制。
更新日期:2021-07-21
down
wechat
bug