AVS 47th International Symposium
    Semiconductors Friday Sessions
       Session SC+EL-FrM

Paper SC+EL-FrM7
Effect of Annealing and Carbon Concentration on the PL Intensity from GaN:Er and GaN:Eu

Friday, October 6, 2000, 10:20 am, Room 306

Session: III-Nitride Processing and Devices
Presenter: M.E. Overberg, University of Florida
Authors: M.E. Overberg, University of Florida
C.R. Abernathy, University of Florida
S.J. Pearton, University of Florida
J.M. Zavada, U.S. Army European Research Office, UK
Correspondent: Click to Email
An attractive alternative for emission in the visible and near-IR are rare earth doped III-Nitrides, whose emission wavelength is host-material insensitive and less susceptible to thermal quenching than conventional narrow gap semiconductors. GaN doped with Er and Eu during growth by molecular beam epitaxy (MBE) has been found to produce strong room temperature emission at 1540 nm and 621 nm, respectively. In addition to the electronic characteristics of the host material, impurities such as C and H are expected to play an important role in the emission process. In this study, the effects of carbon doping and annealing in either nitrogen or forming gas on the luminescence intensity from Er-doped and Eu-doped GaN has been investigated. In samples with no added carbon, annealing was found to decrease the room temperature emission. The addition of carbon to the GaN during growth however, not only improved emission relative to non-carbon doped material but also produced material which improved with annealing. For carbon co-doped material the presence of hydrogen in the annealing ambient produced the greatest improvement in emission intensity, suggesting that both C and H are beneficial to the emission process. The effect of annealing on surface morphology and structural quality will also be presented as will a model for the observed PL behavior.