Experimental arguments for the identity of EL6 with the 0.13 eV donor in bulk n-GaAs

Abstract

Medium-deep electron levels which influence t h e electrical properties of undoped n-GaAs bulk material were investigated both by Schottky junction methods (DLTS, TSCap and C-V) and by the temperature-dependent Hall effect. The resulting activation energies and concentrations imply that the EL6 centre known from DLTS with E, % 0.35 eV is connected with the 0.13 eV donor of TDH.

Activation energies of the EL6 trap and of the 0.15 eV donor and their correlation in GaAs

“…. , 0.20 eV) deviates considerably from the DLTS energy [3,12,13]. This hypothesis is supported by results of Zhao et al [14], that in the case of EL6 the DLTS activation energy E a is composed of the impurity-to-band activation energy E EL6 and of an unusually high value of the activation energy of the capture cross section E σ (0.200 ± 0.025 eV).…”

DX-like properties of theEL6defect family in GaAs

“…6 In particular, temperature-dependent Hall and deep-level transient spectroscopy ͑DLTS͒ measurements have given direct evidence that EL6 plays an important role in the decrease of the resistivity of undoped GaAs crystals. [7][8][9] The work of Chantre, Vincent, and Bois showed that the EL6 defect possessed some interesting properties. 10 In their experiment, it was found that EL6 exhibited very different thermal (ϳ0.3 eV͒ and optical ionization energies (ϳ0.86 eV͒, suggesting a large lattice relaxation ͑LLR͒ effect for this defect.…”