Investigation of electric field effect on defects in GaAsN by admittance spectroscopy

摘要

We use the Arrhenius transformation and matching (ATM) method to extract activation energy and attempt-to -escape frequency of the nitrogen-related defect (E1) in GaAsN from admittance spectroscopy measurements taken at various temperature and electric field. The ATM method is equivalent to the conventional Arrhenius plot and line-fitting (APL) method for Arrhenius processes with temperature-independent E-a and nu(0 )(e.g., E1 in a low electric field and at high temperatures) and advantageous for non-Arrhenius processes with temperature -dependent E-a and nu(0), (e.g., E1 in a high electric field and at low temperatures), where the APL method is not reliable. The ATM method enables a detailed account on how E(a )evolves with the temperature and the electric field in a continuously varying experimental space, which is not possible with the APL method. The evolution of carrier emission behaviors from the E1 defect and a neighboring E2 defect provides experimental evidence of field-induced metastability possibly due to the interaction of two defects with close atomic origins or spatial locations.