Panchromatic cathodoluminescence characterization of III‐V lattice‐mismatched heterostructures

Abstract

Some examples of the possibilities that panchromatic cathodoluminescence (PCL) offers in the scanning electron microscopy (SEM) characterization of III‐V semiconductors are presented. Investigations on lattice‐mismatched InGaAs/InP, InGaAs/ GaAs single heterostructures, and InGaAs/GaAs superlattices and GaAs/Ge and GaAs/InP single layers are shown. Further, the use of PCL as a support in the nondestructive determination of the sensitivity limit of Rutherford backscattering and x‐ray diffraction techniques in the study of strain release in some of the above mentioned heterostructures is presented. Finally, PCL on‐line study of dislocation movement induced by electron beam irradiation in the SEM, as evidence of InGaAs/GaAs superlattice metastability, is also presented.

Cathodoluminescence Spectroscopy of Complex Dendritic Au Architectures for Application in Plasmon‐Mediated Photocatalysis and as SERS Substrates

“…We start by acquiring panchromatic CL maps: the CL signal is integrated over all the wavelengths that fall within the detector range. [ 38 ] Figure a–d (and Figure S2, Supporting Information, for smaller magnification) shows the results of this measurements by overlaying the CL emission (blue spots) onto their respective SEM images (red), clearly demonstrating that the areas of strong CL signal correlate with morphological features of the structure, especially the sharp tips and edges. For 100 s electrodeposition time, we observe faint CL hot‐spots arising predominantly from edges and surfaces of the NPs and nanoclusters, while for electrodeposition times ≥200 s, a strong emission due to excitation of plasmon modes is shown to follow the roughness and the high curvature regions of the architectures.…”

Multipolar and bulk modes: fundamentals of single-particle plasmonics through the advances in electron and photon techniques

“…One of the most useful tools in the CL family of methods is the employment of monochromatic [45,46] and panchromatic [47] excitation. The latter is a rather old [48] method of CL imaging that averages the CL signal over all wavelengths that fall within the detection range. This is an obvious advantage against EELS, as the emitted photons of various wavelengths in CL provide a clear image of the optical behavior of the system under investigation, while the various energies of the inelastic scattering events in EELS cannot be identified with various photon wavelengths, as it is explained in the next part.…”