Thermally-stimulated current measurements were made of an undoped semi-insulating crystal under 1.06μ illumination at 15K. By combining these results with Hall-voltage measurements, it was confirmed that there existed hole traps which exhibited similar activation energies to that associated with the actuator level in the deep acceptor-mediated photo-quenching model for EL2. The observed quenching of these hole traps suggested that the actuator level was probably part of a metastable complex.

Thermally-stimulated current observation of hole traps in undoped semi-insulating GaAs M.Suemitsu, Y.Sagae, N.Miyamoto: Journal of Applied Physics, 1999, 85[6], 3139-41