Emission channeling studies of Pr in GaN

We report on the lattice location of Pr in thin film, single-crystalline hexagonal GaN using the emission channeling technique. The angular distribution of β− particles emitted by the radioactive isotope Pr143 was monitored by a position-sensitive electron detector following 60 keV room temperature implantation of the precursor isotope Cs143 at a dose of 1×1013 cm−2 and annealing up to 900 °C. Our experiments provide direct evidence that Pr is thermally stable at substitutional Ga sites.