Highly regular rosette-shaped cathodoluminescence in GaN selfassembled nanodisks and nanorods  

作　　者：Bijun Zhao Mark Nicolas Lockrey Naiyin Wang Philippe Caroffu Xiaoming Yuan Li Li JenniferWong-Leung Hark Hoe Tan Chennupati Jagadish 

机构地区：[1]Departm ent of Electronic Materials Engineering,Research School of Physics,The Australian National University,Canberra 0200,ACT,Australia [2]Australian National Fabrication Facility,Research School of Physics,The Australian National University,Canberra 0200,ACT,Australia [3]Hunan Key Laboratory for Supermicrostructure and Ultrafast Process,School of Physics and Electronics,Central South University,932 South Lushan Road,Changsha 410083,China [4]ARC Centre of Excellence for Transformative Meta-O ptical Systems,Research School of Physics,The Australian National University,Canberra 0200,ACT,Australia

出　　处：《Nano Research》2020年第9期2500-2505,共6页纳米研究（英文版）

基　　金：B.J.Z.would like to thank the China Scholarship Council and the Australia National University for her scholarship support;X.Y.thanks the National Natural Science Foundation of China(Nos.61974166 and 51702368)for financial support;We would like to thank Dr.Xu Zhang from Zhengzhou University for helpful discussion on some of the strain aspects in this work.

摘　　要：Self-assembled GaN nanorods were grown by metal-organic chemical vapor deposition.A highly regular rosette-shaped cathodoluminescence pattern in the GaN nanorods is observed,where its origin is helpful to deepen the understanding of GaN nanorod growth.The pattern forms at the very early stages of nanorod growth,which consists of yellow luminescence at the edges and the non-luminous region at six vertices of the hexagon.To clarify its origin,we carried out detailed cathodoluminescence studies,electron microscopy studies and nanoscale secondary ion mass spectrometry at both the nanorod surface and cross-section.We found the pattern is not related to optical resonance modes or polarity inversion,which are commonly reported in GaN nanostructures.After chemical composition and strain analysis,we found higher carbon and nitrogen cluster concentration and large compressive strain at the pattern area.The pattern formation may relate to facet preferential distribution of non-radiative recombination centers related to excess carbon/nitrogen.This work provides an insight into strain distribution and defect-related emission in GaN nanorod,which is critical for future optoelectronic applications.

关 键 词：metalorganic chemical vapor deposition(MOCVD) GaN nanorod CATHODOLUMINESCENCE yellow luminescence non-radiative recombination 

分 类 号：TB383[一般工业技术—材料科学与工程]