Abstract. In the present work we have carefully optimized the operation of plasma source and the growth parameters of GaAsN layers. We have demonstrated the possibility of incorporation about 1.5% of N into GaAs without decreasing the photoluminescence intensity.

The optoelectronic characteristics of self-assembled InAs quantum dots ͑QDs͒ with strain-reduced layers ͑SRLs͒ were investigated using photoluminescence ͑PL͒ spectroscopy. Various SRLs that combine In 0.14 Al 0.86 As and In 0.14 Ga 0.86 As with the same total thickness were examined to ascertain their confining effect on carriers in InAs QDs. The emission wavelength is blueshifted as the thickness of InAlAs is increased. The energy separation between the ground state and the first excited state of QDs with InAlAs SRLs greatly exceeds that of QDs with InGaAs SRLs. Atomic force microscopic images and PL spectra of the QD samples demonstrated that high-quality InAs QDs with long emission wavelengths and a large energy separation can be generated by growing a low-temperature, thin InAlAs SRL onto self-assembled QDs.

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Homoepitaxial growth of Si on high-angle miscut (3.0°) Si(111) substrates through an overlayer of Pb is shown to occur at 280 °C. In this work, films can be deposited up to 2000 Å in thickness with no indication that this is an upper limit for high-quality epitaxy. Samples were analyzed using Rutherford backscattering spectrometry and cross-sectional transmission electron microscopy. It is shown that a distinct range of Pb coverage (0.8–1.0 monolayer) results in the best quality growth, with no measurable amount of Pb trapped at either the interface or within the grown films.

Molecular-beam-epitaxy growth of high structural and optical-quality InGaAsN∕GaAs quantum wells (QW) has been investigated. The material quality can be improved significantly by using low-temperature growth to suppress the phase separation. High-performance ridge-waveguide InGaAsN∕GaAs single QW lasers emitting at 1.3μm have been demonstrated. Infinite-cavity-length threshold-current density of 400A∕cm2, internal quantum efficiency of 96%, and a slope efficiency of 0.67W∕A for a cavity length L=1mm were obtained. A TO46 packaging laser shows single lateral-mode kink-free output power of more than 200mW with a maximum total wallplug efficiency of 29% at room temperature under continuous wave (cw) operation. Moreover, 1.3μm InGaAsN∕GaAs QW vertical-cavity surface-emitting lasers with a threshold current density lower than 2KA∕cm2 at room temperature have been achieved. We obtained multimode cw output power and slope efficiency in excess of 1mW and 0.15W∕A, respectively.