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An investigation of first-order Raman scattering of hexagonal GaN single crystal films deposited on sapphire substrate by low pressure metal organic chemical vapour deposition is presented. It was possible to obtain the temperature dependence of the five GaN Raman modes.

A study was conducted to analyze six nominal In(sub 0.48)(Ga(sub 1-x)Al(sub x))(sub 0.52)P layers prepared on GaAs(001). The quaternary alloy was prepared by low pressure metalorganic chemical vapor deposition turbo disk technology. A combination on nondestructive methods was utilized to understanding the growth parameters of the alloy. These include high resolution x-ray diffraction, atomic force microscopy and reflectance anisotropy.

A study was conducted to anlyze semiconductor wafers of both 4H-SiC and 6H-SiC using Raman spectroscopy. The Coherent Model INNOVA 90 Ar/Kr laser was utilized to record the Raman spectra at various spots on each wafer. Results indicated that the phonon-plasmon coupling of the AI(LO)phonon can be utilized as a carrier concentration measure. Findings also showed that Raman scattering of the phonon can be utilized as an in situ, noncontact diagnostic of doping uniformity in the manufacture of semiconductors.

Nonlinear refractive cross-sections were deduced from data related to self-defocusing in ZnTe across a range of wavelengths observed below the band edge. The deduced nonlinear refraction cross-section values corresponded to those obtained from a band-filling model.

A vibration analysis is presented of piezodriven pipette in the microinjection when different liquids are used as the plug inside the pipette as the fluid surrounding the pipette. Results reveal that mercury does significantly affect the vibration characteristics of the injection pipette, namely, the resonance frequency of the pipette is significantly lower.

Provides information on a study which offered a way to optimize growth parameters to produce high crystalline quaternary alloy. Evaluation of the epitaxial films and growth processes; Information on the sample crystalline quality; Study of the surface morphology of the quaternary compounds; Experimental results.

The alloy system InxGa(sub1-x) is important in both science and technology, and studies have so far concentrated on its properties and on device performance and characterization. A spectroscopic study of the properties of InxGa(sub1-x)N epitaxial films grown on thick GaN epilayers has been undertaken. The optical spectra of InGaN alloys has large linewidths and large Stokes shifts between PL and PR transition energies. The alloying of InN with GaN results in drastic optical changes.