Optical Performance of Top-Down Fabricated AlGaN Nanorod Arrays with Multi-Quantum Wells Embedded

• Main Authors: Shucheng Ge, Jiangping Dai, Na Gao, Shiqiang Lu, Penggang Li, Kai Huang, Bin Liu, Junyong Kang, Rong Zhang, Youdou Zheng
• Format: Article
• Language: English
• Published: SpringerOpen 2019-05-01
• Series: Nanoscale Research Letters
• Subjects: DUV AlGaN multi-quantum wells; Nanorod light-emitting diodes; Internal quantum efficiency; Light extraction
• Online Access: http://link.springer.com/article/10.1186/s11671-019-3003-1
• ISSN: 1931-7573; 1556-276X

Abstract Deep ultraviolet AlGaN-based nanorod (NR) arrays were fabricated by nanoimprint lithography and top-down dry etching techniques from a fully structural LED wafer. Highly ordered periodic structural properties and morphology were confirmed by scanning electron microscopy and transmission electron microscopy. Compared with planar samples, cathodoluminescence measurement revealed that NR samples showed 1.92-fold light extraction efficiency (LEE) enhancement and a 12.2-fold internal quantum efficiency (IQE) enhancement for the emission from multi-quantum wells at approximately 277 nm. The LEE enhancement can be attributed to the well-fabricated nanostructured interface between the air and the epilayers. Moreover, the reduced quantum-confined stark effect accounted for the great enhancement in IQE.