Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group
Journal Home About Issues in Progress Current Issue All Issues Early Posting Feature Issues

Scanning electron microscopy as a flexible technique for investigating the properties of UV-emitting nitride semiconductor thin films

C. Trager-Cowan, A. Alasmari, W. Avis, J. Bruckbauer, P. R. Edwards, B. Hourahine, S. Kraeusel, G. Kusch, R. Johnston, G. Naresh-Kumar, R. W. Martin, M. Nouf-Allehiani, E. Pascal, L. Spasevski, D. Thomson, S. Vespucci, P. J. Parbrook, M. D. Smith, J. Enslin, F. Mehnke, M. Kneissl, C. Kuhn, T. Wernicke, S. Hagedorn, A. Knauer, V. Kueller, S. Walde, M. Weyers, P.-M. Coulon, P. A. Shields, et al.

Open Access Open Access

Abstract

In this paper we describe the scanning electron microscopy techniques of electron backscatter diffraction, electron channeling contrast imaging, wavelength dispersive X-ray spectroscopy, and cathodoluminescence hyperspectral imaging. We present our recent results on the use of these non-destructive techniques to obtain information on the topography, crystal misorientation, defect distributions, composition, doping, and light emission from a range of UV-emitting nitride semiconductor structures. We aim to illustrate the developing capability of each of these techniques for understanding the properties of UV-emitting nitride semiconductors, and the benefits were appropriate, in combining the techniques.

Published by Chinese Laser Press under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Full Article  |  PDF Article

Corrections

18 November 2019: A typographical correction was made to the article title.

More Like This
Direct demonstration of carrier distribution and recombination within step-bunched UV-LEDs

Houqiang Xu, Jiean Jiang, Li Chen, Jason Hoo, Long Yan, Shiping Guo, Cai Shen, Yanping Wei, Hua Shao, Zi-Hui Zhang, Wei Guo, and Jichun Ye
Photon. Res. 9(5) 764-771 (2021)

Multi-step in situ interface modification method for emission enhancement in semipolar deep-ultraviolet light emitting diodes

Li Chen, Jie Sun, Wei Guo, Jason Hoo, Wei Lin, Hangyang Chen, Houqiang Xu, Long Yan, Shiping Guo, Junyong Kang, and Jichun Ye
Photon. Res. 10(12) 2778-2785 (2022)

Improved performance of UVC-LEDs by combination of high-temperature annealing and epitaxially laterally overgrown AlN/sapphire

Norman Susilo, Eviathar Ziffer, Sylvia Hagedorn, Leonardo Cancellara, Carsten Netzel, Neysha Lobo Ploch, Shaojun Wu, Jens Rass, Sebastian Walde, Luca Sulmoni, Martin Guttmann, Tim Wernicke, Martin Albrecht, Markus Weyers, and Michael Kneissl
Photon. Res. 8(4) 589-594 (2020)

View More...

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)
Fig. 1.
Fig. 1. ECCI micrograph from AlGaN thin film.

Download Full Size | PDF

Fig. 2.
Fig. 2. (a) SE image of nPSS, (b) schematic of overgrowth of AlN on nPSS, and (c) ECCI micrograph from an AlN thin film. Inset is on the same scale but with higher resolution.

Download Full Size | PDF

Fig. 3.
Fig. 3. EBSD maps from the AlN/nPSS thin film: (a) grain reference orientation deviation (GROD) map and (b) GROD axis map relative to the sample normal (c-axis, [0001] direction]) where the colors denote direction of in-plane rotation (i.e., around the c-axis). The red regions are rotated in the opposite direction to the blue regions as indicated.

Download Full Size | PDF

Fig. 4.
Fig. 4. (a) Schematic of semi-polar GaN microrod template and overgrowth, indicating the distribution of stacking faults on the surface of the sample and the crystallographic directions. (b) ECCI micrograph revealing stacking faults. (c) Example CL spectra from a dark stripe and a bright stripe, respectively. The boxes on (d) indicate where the spectra were extracted from the CL dataset. (d) Integrated CL intensity image of the GaN near band edge (NBE) emission (3.15–3.50 eV) on the same scale as (e) but not from the same area. (e) Higher resolution ECCI micrograph revealing dislocations. (f) Integrated CL intensity image of the GaN near band edge (NBE) emission (3.15–3.50 eV) on the same scale as (e) but not from the same area.

Download Full Size | PDF

Fig. 5.
Fig. 5. (a) Schematic of the sample structure. x = 0.82 for the top 1.6 μm layer. (b) Atomic force microscopy image of the sample surface. (c) ECCI micrograph (the black brackets indicate “stripes” of higher dislocation density in the coalescence region). (d) Topographic image. (c) CL near band edge (NBE) peak intensity map. (d) NBE CL peak energy map. Images (c) to (f) were acquired from approximately the same region of the sample. The white arrows indicate the apexes of the hillocks. The CL peak intensity and peak energy were extracted from hyperspectral data.

Download Full Size | PDF

Fig. 6.
Fig. 6. WDX maps of the intensities of (a) Ga L α (left) and (c) Al K α (right) X-rays, and (b) a backscattered electron image (center) of a micrometer-scale region of a c-plane AlGaN sample, with an average AlN content of 81%. The scale bar for X-ray intensities applies to both WDX maps, although with different absolute values.

Download Full Size | PDF

Fig. 7.
Fig. 7. (a) Semi-log plot showing the measured Si content in the GaN layers, calibrated using the points where SIMS data is available (red data points). (b) Long qualitative scan for Si for the sample with lowest measured Si content 2.3 × 10 17   cm − 3 , using a TAP crystal showing the WDX Si peak.

Download Full Size | PDF

Select as filters
Select Topics Cancel
Top
       
© Copyright 2024 | Optica Publishing Group. All rights reserved, including rights for text and data mining and training of artificial technologies or similar technologies.
Privacy | Terms of Use