A novel hybrid pulsed laser deposition/metalorganic vapour deposition method to form rare-earth activated GaN

A novel low-temperature method based on a combination of pulsed laser deposition and metalorganic chemical vapour deposition was used to fabricate GaN thin films doped with rare-earth (RE) ions. The films were deposited on GaN/Al₂O₃ substrates. The x-ray diffraction analysis of these GaN : RE (RE = Eu, Tb) samples showed that the films have the hexagonal phase of GaN and are polycrystalline with strong texture along the [0 0 1] direction. Cathodoluminescence spectra acquired at room temperature show the near band edge emission of GaN and the corresponding emission lines of the intra-shell transitions of either Eu³⁺ or Tb³⁺ ions.