Abstract:
Inductively coupled Ar plasma etching of n-type (Si doped) Gallium Arsenide (GaAs) introduces
several electron traps, Ec – 0.04 eV (labelled E10), Ec – 0.19 eV, Ec – 0.31 eV, Ec – 0.53 eV, and
Ec – 0.61 eV (behaving like the well documented M3 and labelled M30 in this study), of which the
metastable defects Ec – 0.04eV (E10 ), and Ec – 0.07 eV are novel. Furthermore, E10 and M30 exhibit
strong field enhanced carrier emission. Double-correlation deep level transient spectroscopy was
used to investigate the field dependent emission behaviour of these two defects. It is shown that for
both traps, the observed enhanced emission is due to phonon assisted tunnelling. The latter
observation is contrary to the literature reports suggesting that enhanced carrier emission for M3
occurs via the Poole-Frenkel mechanism.
