Characterization of defect states in Ga-rich gallium arsenide crystals by thermally stimulated current

Abstract

The trap levels in Ga-rich GaAs crystals were studied in the temperature range of 10–300 K using thermally stimulated currents (TSC) technique. During the experiments we utilized a constant heating rate of 0.2 K/s. Experimental evidence is found for two electron trapping centers in the crystal with activation energies of 44 and 50 meV. The analysis of the experimental TSC curve suggests slow retrapping. The capture cross sections of the traps were determined as 8.8 × 10−25 and 1.0 × 10−25 cm2 with concentrations of 2.7 × 1011 and 1.3 × 1011 cm−3, respectively.