The effect of rapid thermal annealing on GaNAs films, grown onto GaAs (100) substrates by radio-frequency plasma-assisted solid-source molecular beam epitaxy, was investigated by using low-temperature photoluminescence and high-resolution X-ray diffraction measurements. Samples of GaNAs, with N contents of 1.3 and 2.2% (determined by experimental curve-fitting of X-ray rocking curves and dynamic diffraction theory), exhibited an overall blue-shift in energy of 0.0677eV and an intermediate red-shift of 0.0422eV in the photoluminescence spectra when subjected to

rapid thermal annealing (525 to 850C, 600s). The results suggested that the GaNAs layer may have undergone intermediate substitutional–interstitial diffusion in addition to pure out-diffusion of N atoms. Samples which were annealed at 700 to 750C exhibited a 1.7 to 2.1 times improvement in the integrated photoluminescence intensity and a 1.6 to 1.8 times reduction in the photoluminescence full-width at half-maximum; as compared with as-grown samples. The high-resolution X-ray diffraction results revealed no significant changes in GaNAs lattice parameter between as-grown and annealed samples. This indicated that the samples were thermally stable; with low overall N out-diffusion.

Rapid Thermal Annealing of GaNxAs1–x Grown by Radio-Frequency Plasma Assisted Molecular Beam Epitaxy and its Effect on Photoluminescence. W.K.Loke, S.F.Yoon, S.Z.Wang, T.K.Ng, W.J.Fan: Journal of Applied Physics, 2002, 91[8], 4900-3