ABSTRACT
In Te-doped and O-doped GaAs middle resistivity samples, combined photoexcited Thermally Stimulated Current (TSC), Thermal Admittance Spectroscopy (TAS) and Deep Level Transient Spectroscopy (DLTS) measurements were carried out. In the temperature range between 250 K to 290 K a negative peak in the TSC and an emission in the TAS spectrum occurs which is identified as the EL3 level. Both spectra show a strong dependence on the reverse voltage. Furthermore a photoinduced capture process in the TAS spectrum was found in the same temperature region under illumination. The results are discussed in terms of a photoinduced transition from a trap to a metastable state during the excitation and a capture process in the temperature range from 250 K to 290 K. This process is controlled by the position of the Fermi level. The metastable OAs − defect state is discussed as participating traps.
