Effect of atomic hydrogen on Er luminescence from AlN

AlN(Er) doped with Er during metal organic molecular beam epitaxy has been plasma hydrogenated in situ at 200-250 degrees C using an electron cyclotron resonance source. By isotopic substitution of H-2 for H-1, we have found from secondary ion mass spectrometry profiling that a 30 min hydrogenation treatment can incorporate similar to 2 X 10(19) cm(-3) deuterium atoms to depths greater than or equal to 1 mu m. The intensity of the 1.54 mu m Er3+ luminescence is increased by a factor of similar to 5 by the 200 degrees C hydrogenation, and this effect is thermally stable to 300 degrees C, indicating a binding energy of >1.5 eV for hydrogen at defects in the AlN. These defects would normally either be recombination centers or provide an alternative de-excitation path for the Er. We have previously found that AlN provides the best resistance to thermal quenching of Er luminescence of any semiconductor due to its wide bandgap. Together, these results suggest that AIN(Er) may be a promising material for optical control of devices such as light-triggered SiC or GaN thyristors for power switching applications, where a fiber-transmitted signal from temperature-tolerant material is necessary in controlling power distribution grids. Hydrogen does not leave the AlN until similar to 800 degrees C and presumably forms an intermediate state such as H-2 or larger clusters prior to evolution from the surface, and again this stability is among the best for any semiconductor. (C) 1998 American Vacuum Society.