Cathodoluminescence and photoluminescence spectroscopies have been performed on hexagonal boron nitride powders. The combination of these techniques allows us to analyze the two observed luminescence bands. A deep-level UV emission at about 4 eV is attributed to defects or impurities, and a... (Read more)

The optical properties of vertically stacked self-assembled GaN/AlN quantum dots (QD's) grown on Si substrates were studied by means of temporally and spatially resolved cathodoluminescence (CL). An analysis of the CL spectra, thermal activation energies, and measured decay times of the QD... (Read more)

White electroluminescence from carbon- and silicon-rich silicon oxide layers is reported. The films were fabricated by Si and C ion implantation at low energy in 40 nm thick SiO₂, followed by annealing at 1100 °C. Structural and optical studies allow assigning the... (Read more)

In this work, we present a detailed cathodoluminescence characterization of GaInNAs quantum wells grown on GaAs(111)B. As-grown and annealed InGaAs and GaInNAs quantum wells were maeasured and compared by spatially resolved cathodoluminescence at different photon energies. In the case of... (Read more)

The authors present a low voltage cathodoluminescence (CL) study of as grown GaN and GaN:Si epilayers on sapphire. At 1 kV they resolve individual threading dislocations on the sample surface at low temperature (5 K), which appear as correlated dark spots. Analysis of CL intensity profiles across... (Read more)

The authors report on the observation of electroluminescence (EL) in CuGaSe₂ solar cells using tapping-mode atomic force microscopy based on tuning-fork sensors. Individually injected current pulses are seen during intermittent contact driven by an external bias applied to the conducting... (Read more)

The rate of spectral shift with applied biaxial stress [piezospectroscopic (PS) coefficient] was determined for the electron-stimulated F⁺ luminescence emitted from the c plane of sapphire (-Al₂O₃) as =1.18±0.03 nm/GPa. The PS dependence could be... (Read more)

Light-emitting centers in alkali-ion-implanted quartz have been investigated with respect to the solid phase epitaxial growth of the ion irradiation induced amorphous zone. Cathodoluminescence was studied under the conditions of chemical epitaxy in annealing the samples, implanted with... (Read more)

Cathodoluminescence (CL) and photoluminescence (PL) properties are studied on neodymium (Nd)- and dysprosium (Dy)-ion-implanted 4H–SiC. No appreciable CL and PL can be observed for all as-implanted samples. Strong visible CL due to Nd³⁺ and Dy³⁺ is observed only after... (Read more)

Hydrogen-vacancy related defect (H1) in chemical vapor deposition homoepitaxial diamond films has been investigated by electron paramagnetic resonance and cathodoluminescence. It is found that the concentration of H1 significantly decreases as the dilution... (Read more)

A microscopic procedure has been proposed for evaluating the stress dependence of the (room-temperature) cathodoluminescence (CL) excitonic band emitted from the (0001) crystallographic plane of GaN in a field-emission-gun scanning electron microscope. The room-temperature near-band-gap emission... (Read more)

Cathodoluminescence (CL) microscopy and spectroscopy have been used to investigate the optical properties of GaN microstructures patterned by Ar⁺ ion irradiation and subsequent photoelectrochemical (PEC) etching. Monochromatic CL images and CL spectra reveal an enhancement of several... (Read more)

Electroluminescence (EL) properties in the ultraviolet (UV) range were studied on Gd-implanted indium tin oxide/SiO₂:Gd/Si metal-oxide-semiconductor light emitting devices. The efficient UV line at 316 nm from Gd³⁺ centers shows a maximum power density of 2 mW/cm²... (Read more)

Only a few years ago, an account of degradation of silicon carbide high-voltage p-i-n diodes was presented at the European Conference on Silicon Carbide and Related Compounds (Kloster Banz, Germany, 2000). This report was followed by the intense effort of multiple groups... (Read more)

An extended vibronic spectrum (up to six phonon replicas) has been measured by low temperature cathodoluminescence in pure c-BN microcrystalline samples obtained by high temperature high pressure method. The zero phonon line, found at 3.573 eV, should be connected to a center identified... (Read more)

The properties of semi-insulating GaN films with the lower part of the film doped with Fe are reported. The 300 K sheet resistivity of the films was 2×10¹⁰ /square with an activation energy of the dark conductivity of 0.5 eV. The Fermi level is also pinned at... (Read more)

High quality ZnO single-crystal films were doped with copper by thermal diffusion, and their luminescent properties were studied by cathodoluminescence spectroscopy. Doping with copper increases the intensity of the green-emission band of the cathodoluminescence spectrum, whose peak, width, and shape at 78 and 300 K remain unchanged. At 4.2 K, a pronounced phonon structure with a phonon energy of 72 meV is detected in the cathodoluminescence green-emission band of the doped samples. In this case, the phonon peaks feature a triplet fine structure instead of the doublet one generally observed. This feature is attributed to radiative recombination of acceptor excitons that are localized at copper atoms and interact with each one of the subbands of the ZnO valence band. An analysis of the experimental data on the film cathodoluminescence and comparative studies of luminescence and electron spin resonance in single crystals allow one to conclude that the uncontrollable copper impurity typically existing in ZnO is responsible for green-emission luminescence in this material. (Read more)

ZnO polycrystals doped with Li, Cu or Al were prepared by solid-state reactions and their cathodoluminescence (CL) and electron spin resonance (ESR) spectra were measured. A strong yellow emission centered at 2.0 eV was observed for the Al-doped specimen and its intensity was higher than that of... (Read more)

The ZnO samples were prepared by firing at 900°C, finely powdered material under different degrees of reduction. Measurements of the green cathodoluminescence (CL) were done by using a vacuum fluorescent display. The g values of ESR spectrum measured from the powders at 77 K were g|| =... (Read more)