Nanoscale EELS analysis ofInGaN∕GaNheterostructures
| Autor: | Adam J. Papworth, Ana M. Sanchez, Mhairi H Gass, Peter Goodhew, Pierre Ruterana |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Physics
Condensed matter physics business.industry Spectrum (functional analysis) Heterojunction Condensed Matter Physics Electron spectroscopy Electronic Optical and Magnetic Materials Optics Distribution (mathematics) Absorption (logic) business Nanoscopic scale Quantum well Energy (signal processing) |
| Zdroj: | Physical Review B. 70 |
| ISSN: | 1550-235X 1098-0121 |
| DOI: | 10.1103/physrevb.70.035325 |
| Popis: | Kramers-Kronig transformations have been used to analyze the low-loss EELS spectrum of $\mathrm{InGaN}∕\mathrm{GaN}$ MWQs from which the ${\ensuremath{\epsilon}}_{2}(E)$ spectrum was extracted. The ${\ensuremath{\epsilon}}_{2}(E)$ spectrum contains information about absorption from the $d$ levels to the conduction bands in $\mathrm{InGaN}∕\mathrm{GaN}$ heterostructures. We have constructed maps of $\mathrm{Ga}$ distributions from the $\mathrm{Ga}$ absorption peak at $\ensuremath{\sim}23\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ instead of using the traditional edges in the energy core loss spectrum. The use of the ${\ensuremath{\epsilon}}_{2}(E)$ spectrum has shown an increased clarity in the information gained, and often the possibility of analyzing the strain within quantum wells that contain defects such as dislocations and $\mathrm{V}$-defects. It is demonstrated that the $\mathrm{Ga}$ inside the quantum wells has a nonhomogeneous distribution using this novel technique. |
| Databáze: | OpenAIRE |
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