Klausmann, E.E.KlausmannSchneider, J.J.SchneiderKaufmann, U.U.KaufmannAlt, H.C.H.C.Alt2022-03-032022-03-031991https://publica.fraunhofer.de/handle/publica/18028310.1103/PhysRevB.43.12106Using comparative local-vibrational-mode and deep-level transient spectroscopy, we have studied the off-center O sub As defect in high-resistivity, undoped GaAs and neutron-transmutation-doped, n-type samples from the same starting material. The results fully support that this defect has a negative-U character. They also reveal that its deeper, two-electron level corresponds to the chemically unidentified EL 3 defect level in GaAs at E sub c -0.58 eV.enEL3 levelEL3 Niveaunegative-UoxygenSauerstoffSI-GaAs621667530journal article