Heavily doped Ga-doped ZnO (resistivity similar to 8 x 10(-4) Omega cm and optical transmittance 96%) were fabricated by radio frequency magnetron sputtering. Post-growth annealing studies in H-2-Ar and pure Ar atmospheres were conducted. No noticeable thermal-induced change in the Ga depth profile or in the Ga chemical state was found in both atmospheres up to 600 degrees C. The Burstein-Moss effect was exhibited in the effective optical band gap, and the cathodoluminescence (CL) photon energy
