Shallow Si donor in ion-implanted homoepitaxial AlN

Abstract

We demonstrate Si as a shallow donor in aluminum nitride (AlN) with an ionization energy of ∼70 meV. The shallow state was achieved by ion implantation of Si into homoepitaxial AlN and a low thermal budget damage recovery and activation process. These results demonstrate that the DX formation may be a kinetically limited process, though being a non-equilibrium process, preventing the Si donor from relaxing to the deep donor state. The room temperature conductivity was measured to be ∼0.05 Ω−1 cm−1, which is one order of magnitude higher than what has been reported for the epitaxially doped or implanted AlN.