Showing papers on "Cathodoluminescence published in 1970"
TL;DR: In this paper, the conduction band structure and alloy composition of In1−xAlxP at ∼300°K were monitored simultaneously to yield conduction bands structure and Alloy composition, respectively.
Abstract: Cathodoluminescence (CL) and x‐ray emission excited by an electron microprobe in In1−xAlxP at ∼300°K have been monitored simultaneously to yield conduction band structure and alloy composition, respectively Efficient single‐line CL, characteristic of direct bandgap recombination, is observed for x between 00 and almost 05 Elsewhere, the CL, characteristic of recombination in indirect bandgap semiconductors, is weak The direct bandgap CL peak has a composition dependence given by hv=134+223x (eV) The bandgap in the alloy is direct for 000≤x<044 with a maximum gap of 233 eV
82 citations
TL;DR: In this article, the emission spectra of cathodoluminescence of Cu, Ag, and Au in,,, and, at room temperature and near 80°K, are presented.
Abstract: Emission spectra of cathodoluminescence of Cu, Ag, and Au in , , , and , at room temperature and near 80°K, are presented. The spectra depend very much on the coactivators used including the alkalies and the halides. The observations indicate the luminescence to be caused by centers containing both activator and coactivator.
79 citations
25 citations
TL;DR: In this paper, the spectral dependence of the photoluminescence and the time decay of the cathodoluminecence are reported for CdSnP2 single crystals for 1.7
Abstract: The spectral dependence of the photoluminescence and the time decay of the cathodoluminescence are reported for CdSnP2 single crystals for 1.7
18 citations
TL;DR: In this article, two orthogonal sets of striations were examined, one consisting of polytype or faulted bands, the other of thickness variations (linear markings) and they showed that in some specimens certain lines in both sets were strong light sources.
Abstract: ZnS platelets crossed by two orthogonal sets of striations were examined. Nomarski optical interference micrographs and scanning electron microscope (SEM) secondary electron micrographs showed that both sets of striations had associated surface topographical features. One set consisted of polytype or faulted bands, the other of thickness variations (“linear markings”). SEM cathodoluminescence micrographs showed that in some specimens certain lines in both sets were strong light sources. In other specimens only polytype interfaces were linear cathodoluminescent sources. SEM charge collection micrographs showed that many of the polytype or faulted bands could produce contrast possibly due to the separation of electron-hole pairs by internal electric fields associated with these defects. Transmission electron microscopy showed that there could be several different types of faulted stacking structures in areas a micron square in striated ZnS.
17 citations
TL;DR: In this paper, the authors used an electron microprobe for the study of local cathodoluminescence in calcite and found that the electronic states involved in cathodluminescent calcite are interpreted on the basis of ligand field theory, the 4A1g,4Eg(G)→6A 1g transition in Mn2+ activator is found to be responsible for the sharp luminescent peak at 5,800 A.
15 citations
TL;DR: In this article, the photoluminescence, cathodolumininescence and reflectivity spectra of CdTe have been studied at liquid nitrogen, hydrogen or helium temperatures.
14 citations
TL;DR: In this paper, the first observation of luminescence in n-type single crystal AlAs grown by vapor phase epitaxy was reported, and it was estimated that the ionization energy of Si donors in AlAs is ∼ 70 meV.
13 citations
TL;DR: In this article, a Langevin approach was used to estimate the lifetime of the excited state of the luminescence centre of a CMT-7 phosphor in the frequency range 1-40 kHz, where the de-excitation process is considered spontaneous and the excitation process was considered analogous to the process of secondary emission.
Abstract: Fluctuations occurring in cathodoluminescence light stemming from a CMT-7 phosphor were measured in the frequency range 01-40 kHz. The observed noise consists of a frequency-independent part corresponding to full shot noise, and a frequency-dependent part. The latter can be considered amplified cathode beam noise, the frequency dependence of which is associated with a lifetime of 28 μs of the excited state of the luminescence centre. The amplification itself is due to the fact that a bombarding electron may excite several luminescence centres, depending on its energy. The theoretical interpretation is based on a Langevin approach considering a two-level model for the luminescence centre. The de-excitation process is considered spontaneous, whereas the excitation process was considered analogous to the process of secondary emission, the noise of which has been calculated by Shockley and Pierce. It is shown that noise measurements are useful for the evaluation of the energy efficiency of phosphors.
12 citations
TL;DR: In this paper, the cross-over composition from direct to indirect band gap is 60(+or-5) mole % GaP, which is in agreement with previous absorption measurements.
Abstract: Photoluminescence excitation and cathodoluminescence on a series of zinc doped alloys in the composition range 56-100 mole % GaP are in agreement with previous absorption measurements which indicate that the cross over composition from direct to indirect band gap is 60(+or-5) mole % GaP.
12 citations
TL;DR: In this paper, the authors report measurements of cathodoluminescence in ternary semiconductors ZnSiP 2 and CdSnP 2 over a temperature range of 10 −100°K using pulsed electron beam excitation.
TL;DR: In this paper, the Schoen-Klasens mechanism of luminescence in II-VI compounds was shown to apply whenever the lowest excited state of the host is a bound state such as (WO2−4)*, (MoO2+4*) (NbO3−4*) and (W O2−3)*, and was further supported by comparison of the CL and PL emission spectra of YVO4 : Eu3+ (0.05%) with host-excited PL.
TL;DR: In this paper, the behaviour of the green edge cathodoluminescence (100 keV) and photolumininescence emission of cadmium sulphide at liquid helium temperatures has been investigated before and after electron irradiation in the 100 400 keV range.
Abstract: The behaviour of the green edge cathodoluminescence (100 KeV) and photoluminescence emission of cadmium sulphide at liquid helium temperatures has been investigated before and after (i) monoenergetic electron irradiation (in the 100 400 keV range), (ii) heat treatments in sulphur vapour and cadmium vapour. The shorter wavelength emission band (5136.5 AA), attributed to the recombination of free electrons with bound holes does not change significantly under electron irradiation at liquid helium temperatures. The longer wavelength emission band (at approximately (5170 AA), attributed to the recombination of bound electrons with bound holes, is enhanced by irradiation with electrons of sufficient energy to displace sulphur atoms and shifts to higher energies.
TL;DR: In this article, the fraction of the incident energy not absorbed by a phosphor has been determined by measuring the rediffusion coefficient and the energy distribution of backscattered electrons.
Abstract: The fraction of the incident energy not absorbed by a phosphor has been determined by measuring the rediffusion coefficient and the energy distribution of backscattered electrons. Measurements for single crystals and powder samples have shown that a large fraction of the electrons scattered back from powder samples have undergone multiple backscattering, resulting in a reduction in the rediffusion coefficient. New estimates of the maximum attainable cathodoluminescence efficiency of ZnS:Ag have been made.
TL;DR: In this paper, the spontaneous emission from GaAs laser diodes fabricated by vapor-phase epitaxy and containing a high degree of compensation in the p-type side of the junction were, in many respects, similar to those previously reported for the cathodoluminescence of homogeneous p type material.
Abstract: The spectra of the spontaneous emission from GaAs laser diodes fabricated by vapor-phase epitaxy and containing a high degree of compensation in the p-type side of the junction are, in many respects, similar to those previously reported for the cathodoluminescence of homogeneous p-type material. The temperature dependence of the spectra of these diodes supports a model where the emission is attributed to radiative transitions between a narrow band of states near the conduction-band edge and an exponential distribution of states extending the valence band into the forbidden gap. An increase in temperature then results in an increase or a decrease in the radiative power output depending on the position of the quasi-Fermi level for electrons relative to the above narrow band of states and a distribution of nonradiative levels below it.
TL;DR: In this paper, a study of the cathodoluminescence of KCl single crystals with an electron probe working in a very high vacuum was performed, and a kinetic analysis showed a close relation between this cathodology and the evolution of the crystal under irradiation, i.e., the density of the colour centres created.
TL;DR: In this paper, a simple, inexpensive, but very effective device for doing cathodoluminescence studies on the JSM I scanning electron microscope is described, which is a simple and inexpensive device.
Abstract: This note describes a simple, inexpensive, but very effective device for doing cathodoluminescence studies on the JSM I scanning electron microscope.
TL;DR: In this paper, photo and cathodoluminescence of three-component alkali-free borate glasses activated by Ce(3+) were investigated and found to have considerably different spectra.
Abstract: : Photo- and cathodoluminescence of three-component alkali-free borate glasses activated by Ce(3+) were investigated and found to have considerably different spectra. Since variation of the temperature does not bring about coincidence of the spectra, the difference must be attributed to the difference in the mechanisms of excitation. Comparison of the effect of variation of activator concentration on the spectra of photo- and cathodoluminescence gives further insight into the mechanisms of photo- and cathode excitation, Varying the composition of the borate glasses has little effect on the spectra. Measurements were made of the decay times of glasses of various compositions with varying activator concentrations and were found to be fairly consistent in value.