Electron paramagnetic resonance spectroscopy of fast neutron-generated defects in GaAs

Abstract
A series of fast neutron‐irradiated GaAs samples (neutron fluence range of 2×1015–2.5×1017 cm2) has been investigated by electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra at 9 GHz exhibit a broad (∼1 kG) Lorentzian singlet at g≊2.09 superimposed on the AsGa quadruplet. The singlet intensity scales linearly with neutron fluence as does that of the quadruplet. The presence of this new defect has not been reported in as‐grown GaAs known to have large concentrations of AsGa defects. EPR measurements at 35, 159, and 337 GHz indicate that the singlet linewidth increases with the microwave frequency.