The effect of GaN thickness inserted between two AlN layers on the transport properties of a lattice matched AlInN/AlN/GaN/AlN/GaN double channel heterostructure

• Published in: Thin solid films Vol. 551; pp. 146 - 152
• Main Authors: Tülek, R., Arslan, E., Bayraklı, A., Turhan, S., Gökden, S., Duygulu, Ö., Kaya, A.A., Fırat, T., Teke, A., Özbay, E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 31.01.2014; Elsevier
• Subjects: AlInN/GaN single; Aluminum nitride; Carrier density; Channels; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Defects and impurities: doping, implantation, distribution, concentration, etc; Double channel; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Exact sciences and technology; Gallium nitrides; Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects); Heterostructures; Materials science; Other semiconductors; Physics; Scattering; Specific materials; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Transport; Transport properties; Transport; Double channel; AlInN/GaN single; Atomic force microscopy; Transport properties; Barrier layer; Hall mobility; Hall effect; XRD; Gallium nitride; Dislocation density; Temperature effects; Size effect; Electron mobility; Carrier mobility; Temperature dependence; Experimental data; Electrical properties; Surface morphology; Aluminium nitride; Layer thickness; Interface roughness; III-V compound; Interfaces; Transmission electron microscopy; Heterostructures; III-V semiconductors
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2013.11.114

One AlInN/AlN/GaN single channel heterostructure sample and four AlInN/AlN/GaN/AlN/GaN double channel heterostructure samples with different values of the second GaN layer were studied. The interface profiles, crystalline qualities, surface morphologies, and dislocation densities of the samples were investigated using high resolution transmission electron microscopy, atomic force microscopy, and high-resolution X-ray diffraction. Some of the data provided by these measurements were used as input parameters in the calculation of the scattering mechanisms that govern the transport properties of the studied samples. Experimental transport data were obtained using temperature dependent Hall effect measurements (10–300K) at low (0.5T) and high (8T) magnetic fields to exclude the bulk transport from the two-dimensional one. The effect of the thickness of the second GaN layer inserted between two AlN barrier layers on mobility and carrier concentrations was analyzed and the dominant scattering mechanisms in the low and high temperature regimes were determined. It was found that Hall mobility increases as the thickness of GaN increases until 5nm at a low temperature where interface roughness scattering is observed as one of the dominant scattering mechanisms. When GaN thicknesses exceed 5nm, Hall mobility tends to decrease again due to the population of the second channel in which the interface becomes worse compared to the other one. From these analyses, 5nm GaN layer thicknesses were found to be the optimum thicknesses required for high electron mobility. •Single and double channel AlInN/GaN heterostructures were grown.•Structural characterization was investigated.•Transport properties and scattering mechanisms were studied.•The optimum thicknesses for high electron mobility were found.