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Modeling and simulation of the SiC epitaxial growth, and doping in a horizontal hot-wall reactor from common precursors (SiH 4 ; C 3 H 8 diluted in H 2 for growth; N 2 and Al(CH 3 ) 3 for n-type and p-type doping) are presented. The growth and doping features of SiC thin layers on both Si-terminated and C-terminated surfaces are analyzed as a function of various inlet source gas conditions, i.e., various C/Si ratios. The role of the actual surface mass fluxes of both Si-containing and C-containing species and their ratio is analyzed and compared to the inlet experimental parameters. It is demonstrated that the doping level resulting from lattice site competition effects can be quantified by the actual C/Si ratio calculated above the growing surface. Moreover, the surface morphology of the epitaxial layer is explained on the basis of the mass fluxes at the growing surface.

The electrical properties of two-dimensional hole gases (2DHGs) in GaN/AlGaN/GaN double heterostructures were investigated. The layers were grown on sapphire substrates and a high-quality bulk GaN substrate. The coexistence of 2DHG and 2D electron gases on both sides of the AlGaN layer was confirmed by Hall effect measurements at 80–460 K. It was also verified that the 2DHGs were generated by negative polarization at the undoped GaN/AlGaN interface, which did not have a doped Mg acceptor. It was also demonstrated that the 2DHG density could be controlled by varying the AlGaN layer thickness and was inversely related to the 2DHG mobility. The measured relation indicated that the 2DHG mobility is mainly limited by phonon scatterings at around room temperature. As a result, the maximum 2DHG mobility of 16 cm2/Vs at 300 K was achieved with a density of 1 × 1013 cm−2.

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