Arrhenius plot of the Be concentration measured by SIMS as a function of the Be cell temperature. The scale of Be concentration is arbitrary, because no SIMS calibration was available for Be in GaN.
Typical low temperature PL spectrum of a Be-doped GaN layer.
Temperature evolution of the transition energy of the near bandgap emissions. The best fit to the FXA variation and the fitting parameters are shown.
Variation of PL spectra with increasing temperature under P = 1mW.
Evolution of PL spectra with increasing excitation power at T = 4K.
Low temperature PL decays of FXA and DAP emissions.
Time resolved PL spectra recorded in 10 ns periods between 0 and 260 ns at 10K.
Intensity variation of the 2.4-2.5 eV band at low temperature with increasing Be concentration.
Low temperature evolution of the 2.4-2.5 eV band with increasing excitation power.
Evolution of the 2.4-2.5 eV band with temperature under P = 1mW.
Low temperature PL decay of the emission at 2.25 eV.
PL-EPR spectrum of a Be-doped GaN layer, measured via the 2.4-2.5 eV band. Inset : high resolution spectrum, showing shallow donors resonances.