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Thermal decomposition of an amido precursor; [Ga2(NMe2)6, Me=CH3] in an ammonia atmosphere yielded nanostructured gallium nitride powder. The x-ray diffraction spectrum of the nanosized gallium nitride exhibited reflections corresponding to the lattice planes of fcc (zinc blende) GaN. High resolution transmission electron microscopy confirmed the cubic structure of the material and evidence of stacking faults within the fcc structure. Infrared spectra showed the characteristic Ga–N stretch at 550 cm−1. Transmission electron microscope measurements indicated that the GaN consisted of ≈50 nm sized particles which in turn are agglomerates of smaller particles with ≈5 nm domain sizes. The photoluminescence (PL) emission spectrum of the GaN was found to be sensitive to the excitation wavelength exhibiting peaks at 378 and 317 nm. The PL excitation spectrum showed resonances in the 200–300 nm region. These PL results suggest the effect of quantum confinement in these GaN particles.

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The aluminum gallium nitride (AlGaN) alloy is uniquely suited for fabricating optoelectronic devices in the ultraviolet and visible bands of the spectrum. Its synthesis in a nanometer scale may potentially open the way for applications such as tunable optoelectronic devices. Presently, results concerning the synthesis and microstructural and optical characterization of nanometer-sized AlGaN imbedded in a poly-methylmethacrylate (PMMA) matrix are reported. Our optical measurement showed that the AlGaN/PMMA nanoparticle/polymer composite efficiently emits in the violet-blue region, while the microstructural characterization confirms the formation of defect-free zinc blende AlGaN nanoparticles.

Articles you may be interested inIon-surface interactions in low temperature silicon epitaxy by remote plasma enhanced chemical-vapor deposition J.Low temperature deposition of silicon nitride films by distributed electron cyclotron resonance plasmaenhanced chemical vapor deposition J. Vac. Sci. Technol. A 13, 2900 (1995); 10.1116/1.579609 Chemical vapor deposition of aluminum from dimethylaluminumhydride (DMAH): Characteristics of DMAH vaporization and Al growth kineticsNearly stoichiometric aluminum and gallium nitride thin films were prepared from hexakis͑dimethylamido͒dimetal complexes, M 2 ͓N͑CH 3 ) 2 ] 6 ͑MϭAl,Ga͒, and ammonia at substrate temperatures as low as 200°C by using low pressure thermal and plasma enhanced chemical vapor deposition ͑CVD͒. Both processes gave films that showed little or no carbon (Ͻ5 at. %͒ and no oxygen (Ͻfew at. %͒ contamination, but in all cases there was hydrogen incorporation. The films were highly transparent in the ultraviolet and visible regions. The barrier properties of the aluminum nitride films in a Si/AlN/Au metallization scheme were examined by using backscattering spectrometry. The growth rate of the aluminum nitride films was as high as 1300 Å /min. Overall, the results suggest that M 2 ͓N͑CH 3 ) 2 ] 6 ͑MϭAl,Ga͒ are promising precursors for low-temperature/ low-pressure thermal and plasma-enhanced CVD of group III nitride thin films.