Observation of a 0.7eV electron trap in dilute GaAsN layers grown by liquid phase epitaxy

Abstract

The growth of GaAsN layers by liquid phase epitaxy, using polycrystalline GaN as the source of nitrogen, is reported. The presence of nitrogen in the grown layer is indicated by a nitrogen-related shoulder in the Fourier transform absorption spectrum and a resultant band-gap reduction of 90meV is measured by optical transmission and photocurrent techniques. Data from photocurrent and photocapacitance measurements show the presence of a 0.7eV electron trap in the material which originates due to nitrogen. Compared with earlier published data on GaAsN, grown by other techniques, the trap is tentatively related to (N–N) defects at As sites.