Electrical properties of nitrogen-related defects in n-type GaAsN grown by molecular-beam epitaxy

Deep Level Transient Spectroscopy (DLTS) and Laplace DLTS (LDLTS) techniques have been employed to characterize electron traps in dilute GaAsN epitaxial layers grown by Molecular Beam Epitaxy (MBE) on n+ GaAs substrates. The GaAsN samples used in this study were silicon doped (n‐type) and contained nitrogen concentrations ranging from 0.2% to 1.2%. The number of electron traps in each sample detected by the DLTS measurements is found to be dependent on the nitrogen contents. Some of the traps have been identified with previously reported (N‐As)spl split interstitial, nitrogen‐split interstitial, EL6‐like interfacial defect and EL3 defect levels. In a control sample without nitrogen we observed only one deep electron emitting level of energy 0.76 eV and no shallow levels have been seen. However, new shallow traps with energies ranging from 0.036 to 0.13 eV have been detected in samples with nitrogen content in the range 0.2% to 0.4%. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)