Nanoscale Cathodoluminescence Spectroscopy Probing the Nitride Quantum Wells in an Electron Microcope

TL;DR

This study employs nanoscale cathodoluminescence spectroscopy combined with electron microscopy to analyze the luminescence properties of InGaN quantum wells, revealing how atomic structure and defects influence their optical behavior.

Contribution

It introduces a nanoscale spectroscopic approach to directly correlate atomic structure with luminescence in nitride quantum wells, advancing understanding of defect effects.

Findings

Luminescence varies with quantum well period and defects.

Composition and bandgap relationships were established.

Defects like dislocations impact luminescence efficiency.

Abstract

To gain a deeper understanding of the luminescence of multiquantum wells and the factors affecting it on a microscopic level, cathodoluminescence combined with scanning transmission electron microscopy and spectroscopy was used to reveal the luminescence of In0.15Ga0.85N five-period multiquantum wells. The composition-wave-energy relationship was established in combination with energy-dispersive X-ray spectroscopy , and the bandgaps of In0.15Ga0.85N and GaN in multiple quantum wells were extracted by electron energy loss spectroscopy to understand the features of cathodoluminescence luminescence spectra. The luminescence differences between different periods of multiquantum wells and the effects on the luminescence of multiple quantum wells owing to defects such as composition fluctuation and dislocations were revealed. Our study establishing the direct correspondence between the atomic structure of InxGa1-xN multiquantum wells and photoelectric properties, provides useful information for nitride applications.