Optical transitions in Pr-implanted GaN

Photoluminescence (PL) spectroscopy has been used to investigate praseodymi um (Pr) related transitions in Pr-implanted GaN. Wurtzite GaN epilayers wer e grown by metalorganic chemical vapor deposition on sapphire substrates an d subsequently ion implanted with Pr to a dose of 5.7x10(13)/cm(2). The imp lanted samples were annealed in nitrogen to facilitate recovery from implan tation related damage. Narrow PL emission bands related to 4f intrashell tr ansitions of the trivalent Pr ion were observed near 650, 950, 1100, and 13 00 nm. The dependence of PL emission on sample temperature, excitation inte nsity, oxygen incorporation, and annealing temperature was systematically s tudied. We find that the PL efficiency increases exponentially with anneali ng temperature up to the maximum temperature of 1050 degrees C applied in t he current study. Furthermore, the PL emission shows no evidence of signifi cant thermal quenching over the sample temperature range of 10-300 K. This thermal stability will have particular advantages for applications in high temperature optoelectronic devices. (C) 1999 American Institute of Physics. [S0003-6951(99)01732-5].