High resolution cathodoluminescence hyperspectral imaging of surface features in InGaN/GaN multiple quantum well structures

Bruckbauer, Jochen; Edwards, P. R.; Wang, Tao; Martin, Robert

doi:10.1063/1.3575573

Cited by 77 publications

(63 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The beam scans across the sample surface, and a 1600 pixel emission spectrum from 300 to 800 nm is recorded for every pixel with a spatial resolution approaching 10 nm. 24 Electron beam energies of up to 10 kV have been used to probe light emission from up to 300 nm below the sample surface. This depth was calculated by Monte Carlo simulations using the CASINO 25 software to estimate the beam voltages required to excite the active regions of the samples.…”

Section: Methodsmentioning

confidence: 99%

Cathodoluminescence studies of chevron features in semi-polar (112¯2) InGaN/GaN multiple quantum well structures

Brasser

Bruckbauer

Gong

et al. 2018

Journal of Applied Physics

View full text Add to dashboard Cite

This version is available at https://strathprints.strath.ac.uk/63662/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's intellectual output. Epitaxial overgrowth of semi-polar III-nitride layers and devices often leads to arrowhead-shaped surface features, referred to as chevrons. We report on a study into the optical, structural, and electrical properties of these features occurring in two very different semi-polar structures, a blueemitting multiple quantum well structure, and an amber-emitting light-emitting diode. Cathodoluminescence (CL) hyperspectral imaging has highlighted shifts in their emission energy, occurring in the region of the chevron. These variations are due to different semi-polar planes introduced in the chevron arms resulting in a lack of uniformity in the InN incorporation across samples, and the disruption of the structure which could cause a narrowing of the quantum wells (QWs) in this region. Atomic force microscopy has revealed that chevrons can penetrate over 150 nm into the sample and quench light emission from the active layers. The dominance of non-radiative recombination in the chevron region was exposed by simultaneous measurement of CL and the electron beam-induced current. Overall, these results provide an overview of the nature and impact of chevrons on the luminescence of semi-polar devices.

show abstract

Section: Methodsmentioning

confidence: 99%

Cathodoluminescence studies of chevron features in semi-polar (112¯2) InGaN/GaN multiple quantum well structures

Brasser

Bruckbauer

Gong

et al. 2018

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…21 CL hyperspectral imaging was performed in a field emission gun scanning electron microscope (FEI Sirion 200) modified for CL spectroscopy. 18 An advantage of the hyperspectral imaging system used is its ability to measure shifts in emission wavelength on a length scale <20 nm, 22 thus enabling precise mapping of CL spectral features. The CL was excited with an electron beam with accelerating voltage of 2 kV, 10 kV, or 30 kV, with the sample held at room temperature.…”

Section: Sample Fabricationmentioning

confidence: 99%

Influence of stress on optical transitions in GaN nanorods containing a single InGaN/GaN quantum disk

Zhuang

Bruckbauer

Shields

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

Articles you may be interested inCross-sectional sizes and emission wavelengths of regularly patterned GaN and core-shell InGaN/GaN quantum-well nanorod arrays J. Appl. Phys. 113, 054315 (2013) Cathodoluminescence (CL) hyperspectral imaging has been performed on GaN nanorods containing a single InGaN quantum disk (SQD) with controlled variations in excitation conditions. Two different nanorod diameters (200 and 280 nm) have been considered. Systematic changes in the CL spectra from the SQD were observed as the accelerating voltage of the electron beam and its position of incidence are varied. It is shown that the dominant optical transition in the SQD varies across the nanorod as a result of interplay between the contributions of the deformation potential and the quantum-confined Stark effect to the transition energy as consequence of radial variation in the pseudomorphic strain. V C 2014 AIP Publishing LLC.

show abstract

“…In recent work~Liu et al, 2009;Bruckbauer et al, 2011;!, we presented CL hyperspectral imaging results in which variations over length scales approaching 20 nm were observed. In this article, we more fully describe the steps we have taken to overcome the high noise level inherent in nanoscale CL hyperspectral images, including aspects of both instrumentation and data treatment.…”

Section: Introductionmentioning

confidence: 99%

High-Resolution Cathodoluminescence Hyperspectral Imaging of Nitride Nanostructures

et al. 2012

Self Cite

View full text Add to dashboard Cite

This version is available at https://strathprints.strath.ac.uk/42421/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Abstract: Hyperspectral cathodoluminescence imaging provides spectrally and spatially resolved information on luminescent materials within a single dataset. Pushing the technique toward its ultimate nanoscale spatial limit, while at the same time spectrally dispersing the collected light before detection, increases the challenge of generating low-noise images. This article describes aspects of the instrumentation, and in particular data treatment methods, which address this problem. The methods are demonstrated by applying them to the analysis of nanoscale defect features and fabricated nanostructures in III-nitride-based materials.

show abstract

High resolution cathodoluminescence hyperspectral imaging of surface features in InGaN/GaN multiple quantum well structures

Cited by 77 publications

References 18 publications

Cathodoluminescence studies of chevron features in semi-polar (112¯2) InGaN/GaN multiple quantum well structures

Cathodoluminescence studies of chevron features in semi-polar (112¯2) InGaN/GaN multiple quantum well structures

Influence of stress on optical transitions in GaN nanorods containing a single InGaN/GaN quantum disk

High-Resolution Cathodoluminescence Hyperspectral Imaging of Nitride Nanostructures

Contact Info

Product

Resources

About