Growth of low‐dislocation‐density AlGaN using Mg‐doped AlN underlying layer

We report on a new technology for growing low-dislocation-density AlGaN in which a Mg-doped AlN underlying layer is used. By growing AlxGa1-xN on AlN:Mg with AlN molar fractions x of 0.3, 0.5 and 0.7, the density of misfit dislocations is much reduced compared with that in the case of growing AlGaN on undoped AlN. In addition, the surface becomes atomically flat. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)