Effect of the barrier growth mode on the luminescence and conductivity micron scale uniformity of InGaN light emitting diodes

In this paper, we present a combined cathodoluminescence (CL) and electron beam induced current (EBIC) study of the optical and electrical properties of InGaN light emitting diodes grown using different active region growth methods. In one device, both the quantum wells and quantum barriers were deposited at their optimum temperatures (2 T), whereas in the other device, each barrier was grown in a two step process with the first few nanometers at a lower temperature (Q2T). It was found that in the Q2T sample, small micron scale domains of lower emission intensity correlate strongly to a lower EBIC signal, whereas in the 2 T sample which has a more uniform emission pattern and an anti-correlation exists between CL emission intensity and EBIC signal.

[1]  M. Hopkins,et al.  Bias dependence and correlation of the cathodoluminescence and electron beam induced current from an InGaN/GaN light emitting diode , 2014 .

[2]  W. A. Phillips,et al.  The impact of gross well width fluctuations on the efficiency of GaN-based light emitting diodes , 2013 .

[3]  E. Yakimov.  Investigation of electrical and optical properties in semiconductor structures via SEM techniques with high spatial resolution , 2012, Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques.

[4]  K. J. Lethy,et al.  Cross-sectional and plan-view cathodoluminescence of GaN partially coalesced above a nanocolumn array , 2012 .

[5]  A. Wark,et al.  Mapping Localized Surface Plasmons within Silver Nanocubes Using Cathodoluminescence Hyperspectral Imaging , 2011, The journal of physical chemistry. C, Nanomaterials and interfaces.

[6]  Tao Wang,et al.  High resolution cathodoluminescence hyperspectral imaging of surface features in InGaN/GaN multiple quantum well structures , 2011, 1102.1835.

[7]  K. Sobczak,et al.  Inhomogeneities of InGaN/GaN MOVPE multi quantum wells grown with a two temperatures process studied by transmission electron microscopy , 2010 .

[8]  N. B. Smirnov,et al.  EBIC and CL studies of ELOG GaN films , 2009 .

[9]  In‐Hwan Lee,et al.  Optimization of InGaN/GaN multiple quantum well layers by a two-step varied-barrier-growth temperature method , 2008 .

[10]  Shuji Nakamura,et al.  Quantum-confined Stark effect on photoluminescence and electroluminescence characteristics of InGaN-based light-emitting diodes , 2008 .

[11]  K. B. Lee,et al.  InGaN/GaN quantum wells with low growth temperature GaN cap layers , 2007 .

[12]  In-Hwan Lee,et al.  A well protection layer as a novel pathway to increase indium composition: a route towards green emission from a blue InGaN/GaN multiple quantum well , 2007 .

[13]  S. Zaitsev,et al.  EBIC measurements of small diffusion length in semiconductor structures , 2007 .

[14]  C. Humphreys,et al.  High quantum efficiency InGaN/GaN structures emitting at 540 nm , 2006 .

[15]  Colin J. Humphreys,et al.  Misfit dislocations in In‐rich InGaN/GaN quantum well structures , 2006 .

[16]  M. Ramsteiner,et al.  Field-dependent nonlinear luminescence response of (In,Ga)N/GaN quantum wells , 2004 .

[17]  C. Humphreys,et al.  GaN-InGaN Quantum Well and LED Structures Grown in a Close Coupled Showerhead (CCS) MOCVD Reactor , 2002 .

[18]  A. Cavallini,et al.  Electron beam induced current, cathodoluminescence and scanning photoluminescence study of GaN layers , 2000 .

[19]  D. Bimberg,et al.  Scanning cathodoluminescence microscopy: A unique approach to atomic‐scale characterization of heterointerfaces and imaging of semiconductor inhomogeneities , 1991 .

[20]  H. Amano,et al.  Effects of the buffer layer in metalorganic vapour phase epitaxy of GaN on sapphire substrate , 1988 .

[21]  M. Holmes,et al.  Growth and optical characterisation of multilayers of InGaN quantum dots , 2012 .