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Amongst the new precursors for the III component in MOVPE there are numerous nitrogen containing compounds. Using those compounds, besides the electrical and optical quality of the grown material, the question of incorporation of nitrogen arises. We presen ...
GaAlAs/GaAs and GaInAs/InP thick layers, single and multiple quantum wells were grown by atmospheric pressure metalorganic vapor phase epitaxy. Auger electron spectroscopy, wedge transmission electron microscopy, x-ray diffraction, low-temperature photolum ...
The principles of gallium arsenide diode lasers are described and the history of developments is sketched. The importance of threshold current density is emphasised and it is shown that confinement of carriers is improved in heterojunctions using gallium-a ...
We present a comparative study, at 300 K and at low longitudinal field, of the DC characteristics and the low-frequency noise in the drain current of GaAs/AlGaAs MODFETs which, ideally, differ only by the doping mode of the AlGaAs layer. The higher 1/f-lik ...
GaAs/AlxGa1-xAs multiple-quantum-well structures with identical well thicknesses (almost-equal-to 119 angstrom) but with different Al contents x in the barrier (x almost-equal-to 0. 1, 0.2, 0.45, and 1) were grown by molecular-beam epitaxy. We report the c ...
An electromagnetic wave detector formed of semiconductor materials includes at least one quantum well in which there is provided a fine layer of a material with a gap width that is smaller than that of the quantum well layer. For example, in the case of a ...
Expts. are described on the pyrolytic and photolytic laser chem. vapor deposition (LCVD) of Ga and GaAs, as well as hybrid deposition of the latter. Pyrolytic Ga deposits change in shape with laser power variations. A deposit in the shape of an annulus of ...
In a recent paper, we measured the hole diffusion length in a single quantum well (SQW) by a novel method using SEM-cathodoluminescence, assuming that the carriers diffuse only in the SQW. This assumption needs to be checked. Therefore, we present here a m ...
The low-temperature direct and indirect optical transitions in double-barrier Al0.3Ga0.7As/AlAs/GaAs single quantum wells, with AlAs widths of 0, 1, and 2 monolayers, have been studied as a function of pressure. It is shown that intense type-II recombinati ...
We report on a bulk GaAlAs mirror which is used as a saturable absorber for subpicosecond pulse generation around 835 nm. The mirror consists of a 200 nm layer of bulk GaAlAs (with approximately 5% Al content) which is grown on a linear Bragg mirror and is ...
