Double-correlation deep-level transient spectroscopy was used to study the electric-field-induced thermal emission of electrons from the EL5 defect in n-type GaAs crystal. Strongly anisotropic electric-field enhancement of this emission, which was the largest for the electric field parallel to the <100> crystallographic direction and the smallest for the <111> configuration, points to the trigonal symmetry of the defect potential and a strong coupling of the defect to the lattice vibronic modes. In view of the revealed results it was argued that a close pair divacancy complex could be responsible for the EL5 defect.

Electric-Field-Enhanced Electron Emission from the EL5 Deep-Level Defect in GaAs. T.Tsarova, T.Wosinski, A.Makosa, Z.Tkaczyk: Materials Science in Semiconductor Processing, 2006, 9[1-3], 351-4