InGaAsN films and InGaAsN/GaAs quantum wells were grown by metalorganic chemical vapor deposition using 1,1-dimethylhydrazine and tetrirybutylarsice as N and As sources, respectively. A photoluminescence peak at 1.22 μm wavelength at low temperature was observed for the In0.26Ga0.74As1−yNy/GaAs quantum wells. X-ray photoelectron spectroscopy investigation on the InGaAsN films demonstrated the success of nitrogen incorporation and provided evidence of the existence of two principle N configurations, indicating the formation of N–In and N–O,H bonds. The addition of N atoms increases the In concentration in InGaAsN wafers, whereas postgrowth annealing results in In diffusion in surface region.

Multiple energy Al+ and C + ions were implanted into 6H-SiC at room temperature (25 • C) and elevated temperature (600 • C), respectively, followed by 1550• C annealing for 30 min. Fourier transform infrared spectroscopy was used to evaluate the optical properties in the mid-infrared range. An effective medium model, taking into account the presence of an implantation-induced amorphous phase, was developed to establish the relationship between the changes of optical properties and modification of structure.Complete amorphization in the implanted layer was evidenced for room temperature implantation but no such case occurred at elevated temperature implantation. Elimination or decrease of the amorphous phase, via 1550• C annealing, was represented by the recovery of reflectance intensity and shape. Some structural and optical parameters, such as layer thickness and phonon damping constants of the amorphized SiC, were derived from fitting to measured data. Our work demonstrated the successful application of the Lorentz-Drude oscillator model in evaluating the lattice quality of the amorphous/crystalline SiC system.

We have performed a combined investigation of experiment and theory on the infrared reflectance from cubic SiC grown on Si by chemical vapor deposition. A damping behavior of the interference fringes away from the reststrahlen band and a dip or notch within the “flat top” are observed from some samples while they does not occur in high quality 3C-SiC/Si samples. The former is interpreted due to an interfacial transition layer existed between SiC-Si and a rough surface, while the latter can be demonstrated by a three-component effective medium model.

A series of ion-implanted 4H-SiC epilayers, Aluminum (Al) – Carbon (C) co-implanted and Al single implanted, have been studied by micro-Raman scattering, Fourier transform infrared (FTIR), and UV-Visible (200-1100 nm) optical transmission (OT) measurements. The damage and amorphization of SiC layer by ion-implantation, and the elimination or suppression of the implantation induced amorphous layer via high temperature annealing are evidenced. The recovery of the crystallinity and the activation of the implant acceptors are confirmed. Theoretical simulations on the spectroscopic features, for FTIR reflectance spectra, are performed based upon the structural model. The results from different ion implantation conditions are compared. This work also provides a non-destructive and convenient way to investigate the effects of ion implantation/annealing on SiC materials.

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