Growth, doping and characterization of epitaxial thin films and patterned structures of AlN, GaN, and AlxGa1−xN

Abstract

Abstract Advancements in the doping of GaN and AlxGa1−xN thin films, and the growth of GaN and AlxGa1−xN structures on patterned heterostructure substrates via metalorganic vapor phase epitaxy are reported. The acceptor-type behavior of Mg-doped GaN films grown in N2 diluents is presented. Net ionized impurity concentrations up to 8×1018 cm−3 and Hall mobilities up to ≈14 cm2 V−1 s−1 were measured for Mg-doped films grown in N2 in the as-grown condition. Donor and acceptor doping of AlxGa1−xN alloys was performed. Acceptor doping of AlxGa1−xN for x≤0.13 and donor doping for x≤0.58 were achieved for films deposited at 1100 °C. Lateral epitaxial overgrowth of GaN and AlxGa1−xN layers was investigated. The growth and coalescence of GaN and AlxGa1−xN stripes patterned in SiO2 and/or SiNx masks deposited on GaN, including aligned second lateral epitaxial overgrowth on initial laterally overgrown GaN layers, are discussed.