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Photoconductors based on V-grooved Al[sub 0.5]Ga[sub 0.5]As/GaAs multiple quantum wires (QWR) were fabricated. The geometric structure of the QWR was carefully characterized by transmission electron microscopy and spatially resolved microphotoluminescence measurements. Infrared response at 9.2 μm is observed from the photocurrent spectrum measured at 80 K. It is attributed as the intersubband transition in the quantum wire region. Due to the effective quantum confinement from the two (111)-surfaces forming the V groove, the overlapping between the ground state in the QWR and the one in the vertical quantum well is very small. This explains the weak photocurrent signal from the QWR photodetector. Theoretical design for a better wave function overlapping and optical coupling is outlined from the analysis of two-dimensional spatial distributions of the wave functions. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies the asymmetric double GaAs/AlGaAs V-grooved quantum wires, grown by low pressure metalorganic chemical vapor deposition using photoluminescence spectroscopy. Selective treatment of the structure by ion implantation at different arsenic doses after growth; Reduction of the efficiency of the emissions from the implanted well regions.

Deals with the nucleation of semicircular misfit dislocations from the epitaxial surface in strained-layer heterostructures. Suggestions for the misfit dislocation of nucleation mechanisms; Theoretic considerations; Conclusion.

Presents a study which theoretically considered equilibrium geometries dissociated misfit dislocations using elastic theory. Discussion on the perfect glide dislocation in semiconductor materials; Description of the schematic diagram of the dissociated misfit dislocation configuration; Equation of equilibrium dissociation; Method used in obtaining experimental data about the misfit dislocation geometry.

Presents a study which examined the position of misfit dislocations with respect to the strained interface in [001] In[sub0.1]Ga[sub0.9]As/GaAs single heterostructures using transmission electron microscopy. Results of diffraction contrast investigations from plan-view specimens; Analysis of the effect of the strain associated with interfacial steps; Interaction between neighboring misfit dislocations.

Presents a theoretical consideration of the nucleation of misfit dislocations through the extension of dissociated dislocations in the strained interface. General critical thicknesses for dissociated dislocation; Calculation of strained-layer heterostructures; Conclusions.

Presents a study that investigated the onset of misfit dislocation generation and determined the critical thickness for InGaAs/GaAs single heterostructures and single quantum wells. Description of study design using transmission electron microscopy through the epitaxial lift-off technique; Analysis of the geometries of the dislocations in both cases; Comparison between the predicted and the experimental critical thicknesses.

Deals with electron optical characterization of cubic boron nitride (c-BN) thin films prepared by reactive ion plating. Types of electron optical techniques that can be used in the characterization of boron nitride thin films; Model for the formation of c-BN assisted by compressive stress.

Presents a study that investigated the structure and properties of ion-beam-synthesized boron nitride films. Experimental procedures; Results; Discussion.

Presents a study of the enhancement of interdiffusion in GaAs/A1GaAs quantum wells due to anodic oxides. Effects of intermixing on the quantum well shape; What prompted an increase in the intermixing; Information on the effect injection of defects had on the intermixing; Experiments conducted in this study; Results of this study.

Deals with a study which investigated the effect of intermixing on the structural and optical properties of stacked gallium arsenide (GaAs) quantum wire structures on a sawtooth-type nonplanar GaAs substrate. Experimental details; Results and discussion; Conclusion.

Presents a study that investigated the nature of ion damage buildup and amorphization in GaAs-Al[subx]Ga[sub1-x]As multilayers at liquid-nitrogen temperature for a variety of compositions and structures. Dynamic annealing in AlGaAs and at GaAs-AlGaAs interfaces; Background on electrical, optical and band-gap properties of lattice-matched GaAs-AlGasAs heterostructures; Schematic of the various multilayer structures.

Reports on the precise determination of the periodicity for molybdenum/silicon (Mo/Si) and tungsten/carbon (W/C) metallic multilayers by electron and x-ray diffraction. Fabrication of Mo/Si and W/C multilayer films by magnetron sputtering; Determination of the modulation wavelength of the multilayer; Refraction corrections to the Bragg condition for electron and x-ray diffractions.

Presents a study that investigated the ion damage buildup and amorphization processes in Al[subx]Ga[sub1-x] As. Experimental procedures for the preparation of the structures; Interpretation of the Rutherford backscattering spectra for gallium arsenide and the samples of different aluminum compositions; Summary of the damage buildup data for materials of different aluminum compositions.