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AlInN layers with a thickness of 100nm were grown by metal organic vapor phase epitaxy on GaN buffer layers on Si(111) substrates. By varying the growth temperature, In and NH3 flows, and reactor pressure, three series with different In contents were produced and thermally treated in the temperature range from 30to960°C. The as grown and annealed layers were investigated by x-ray diffraction in standard and grazing incidence geometry. Nearly lattice matched samples with an indium concentration of 17%–18% show long time stability at annealing temperatures as high as 960°C. At higher temperatures, the onset of severe Ga–Si meltback etching prevents further measurements. Nonlattice matched samples consist of pseudomorphic and relaxed parts. In the latter, a redistribution and loss of indium is observed upon annealing.

High indium content ([In>]25%) AlInN/GaN multi quantum well structures grown by metal organic vapor phase epitaxy were analyzed by X‐ray diffraction, X‐ray reflection, and photoluminescence measurements. The samples, which exhibit an excellent crystalline quality and smooth interfaces, are found to show broad luminescence below the GaN‐bandgap which shifts with increasing indium content to longer wavelength. At elevated indium content an additional broadening of the luminescence band has been observed. A comparison of the AlInN bandgap and the luminescence energies shows a pronounced stokes shift. XPS measurements reveal a staggered band lineup in Al1‐xInxN /GaN heterostructures with x > 0.25 is found. These findings indicate an indirect transition from the AlInN conduction to the GaN valence band as origin of the luminescence behavior. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

In this work metalorganic chemical vapor phase epitaxy (MOVPE) growth and characterization of AlInN in the whole compositional range and the impact on the development of field effects transistors (FET) structures will be presented. Due to the large difference in the lattice parameters of the binaries AlN and InN the growth of AlInN with high indium concentrations is ambitious, and first the growth conditions for the alloy will be discussed. An experimental phase diagram and corresponding theoretical calculations will be displayed. The critical layer thickness of AlInN on GaN has been experimentally determined. Relaxation of the AlInN-layer has a strong influence on the sample morphology. At indium concentration exceeding 30% an polarization induced hole gas is expected at the AlInN/GaN interface from theoretical calculations, but no p-channel conductivity could be confirmed. The absence of the two dimensional hole gas will be discussed.