Acceptor and donor doping of AlxGa1−xN thin film alloys grown on 6H-SiC(0001) substrates via metalorganic vapor phase epitaxy
Authors: Davis, R.; Bremser, M.; Perry, W.; Nam, O.; Griffis, D.; Loesing, R.; Ricks, D.
Source: Journal of Electronic Materials, Volume 27, Number 4, April 1998 , pp. 229-232(4)
Abstract:Thin films of Si-doped AlxGa1−xN (0.03≤x≤0.58) having smooth surfaces and strong near-band edge cathodoluminescence were deposited at 0.35–0.5 µm/h on on-axis 6H-SiC(0001) substrates at 1100°C using a 0.1 µm AlN buffer layer for electrical isolation. Alloy films having the compositions of Al0.08Ga0.92N and Al0.48Ga0.52N exhibited mobilities of 110 and 14 cm2/V·s at carrier concentrations of 9.6×1018 and 5.0×1017 cm−3, respectively. This marked change was due primarily to charge scattering as a result of the increasing Al concentration in these random alloys. Comparably doped GaN films grown under similar conditions had mobilities between 170 and ∼350 cm2/V·s. Acceptor doping of AlxGa1−xN for x≤0.13 was achieved for films deposited at 1100°C. No correlation between the O concentration and p-type electrical behavior was observed.
Document Type: Research Article
Publication date: 1998-04-01