Influence of photoexcitation on hopping conduction in neutron- transmutation-doped GaAs

TLDR: In this article, the authors studied the tunneling assisted hopping conduction in GaAs under photoexcitation with a photon energy of 1.32 eV and found that the dopants activated by annealing around 400 °C provided the electrons to the defect levels originating the hop conduction even when under photo-excitation.

Abstract: The nature of the tunneling‐assisted hopping conduction in neutron‐transmutation‐doped GaAs has been studied under photoexcitation with a photon energy of 1.32 eV. It is found that the dopants activated by annealing around 400 °C provide the electrons to the defect levels originating the hopping conduction even when under photoexcitation. The hopping conduction under photoexcitation is affected by quenching in photoconductance below 120 K concerned with the main electron trap (EL2) and/or the As antisite defect (AsGa) induced by the neutron irradiation. The photoconductance of the samples with a lower radiation damage, AsGa≤1×1018 cm−3, consists of the coexistence of the hopping and band conductions.