Nanofocused x-ray beams applied for mapping strain in core-shell nanowires
Author
Summary, in English
The core-shell nanowires have the promise to become the future building blocks of light emitting diodes, solar cells and quantum computers. The high surface to volume ratio allows efficient elastic strain relaxation, making it possible to combine a wider range of materials into the heterostructures as compared to the traditional, planar geometry. As a result, the strain fields appear in both the core and the shell of the nanowires, which can affect the device properties. The hard x-ray nanoprobe is a tool that enables a nondestructive mapping of the strain and tilt distributions where other techniques cannot be applied. By measuring the positions of the Bragg peaks for each point on the sample we can evaluate the values of local tilt and strain. In this paper we demonstrate the detailed strain mapping of the strained InGaN/GaN core-shell nanowire. We observe an asymmetric strain distribution in the GaN core caused by an uneven shell relaxation. Additionally, we analyzed the local micro-tilt distribution, which shows the edge effects at the top and bottom of the nanowire. The measurements were compared to the finite element modelling and show a good agreement.
Publishing year
2015
Language
English
Pages
95920-95920
Publication/Series
Proceedings of SPIE
Volume
9592
Document type
Conference paper
Publisher
SPIE
Topic
- Nano Technology
Keywords
- Nanowires
- strain mapping
- nanofocused X-rays
- InGaN
Conference name
Conference on X-Ray Nanoimaging - Instruments and Methods II
Conference date
2015-08-12 - 2015-08-13
Status
Published
ISBN/ISSN/Other
- ISSN: 0277-786X
- ISSN: 1996-756X