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The interaction of chemical vapor deposition (CVD) diamond films with atomic oxygen (AO) produce by radio frequency (rf) oxygen plasma is analyzed. The diamond surface is not completely regenerated after annealing and in situ exposure to thermally activated hydrogen, because of the irreversible deterioration of the surface by AO.

This article investigated the structural, transport, and magnetic properties of a series of samples in which the La(sub 0.67)Sr(sub 0.33)MnO3 (LSMO) layer thickness is fixed at eight unit cells and that of YBa2Cu3O7(YCBO) varied from one to six cells. Magnetic moment measurements present a qualitative agreement with the model.

In this study, damage evolution on Sm and O sublattices in gold implanted samarium titanate pyrochlore was studied by Rutherford backscattering spectroscopy and nuclear reaction analysis. The results showed that the atomic disorder on both the Sm and O sublattices increase nonlinearly with ion influence, eventually achieving a fully amorphous state.

In this article, the Raman signal of CdSe nanocrystals well dispersed in a very thin SiO2 film has been investigated by surface plasmon excitation in a resonant Raman spectroscopy experiment. The luminescence has been measured and its dependence with the separation between the metal layer and CdSe nanocrystals is analyzed.

The fictive temperature (T(sub f) ) and fluorine concentration dependence of structure fluctuation in SiO2 glass were investigated by small-angle x-ray scattering measurement, in this study. It was found that density fluctuation solely contributes to the T(sub f) dependence of structure fluctuation.

The ion-induced secondary electron emission behavior of the resultant thin film of the MgO films prepared using two gels is investigated. The low processing temperature of nonhydrolyzed MgO films revealed that the sol-gel process is suitable to prepare MgO films for use as a protective layer in alternating current plasma display panel cells.

Research is presented concerning the development of a simulation of the passage of O+ and Si+ signals through a transient region before they attain a stationary state, as found in secondary ion mass spectrometry.

Improvement of actinometry and comparison with laser spectroscopy is undertaken in relation to detection of atomic oxygen.

Research into the concentration of interstitial oxygen in silicon is presented. The conversion factors between room and low temperature absorption were determined with an accuracy down to 3%.

The electronic band structure of beta-Ga2O3 is explained and the properties and formation of oxygen vacancies are examined based on semiempirical quantum-chemical calculations. The formation energies and the equilibrium geometries of neutral and ionized oxygen vacancies were also measured, after which the high temperature n-type conduction is discussed using the calculated donor level positions of the oxygen vacancies.

Research was conducted to examine oxygen precipitation and secondary defects in silicon by high energy ion implantation and two-step annealing. The two-step annealing method was used to analyze the oxygen precipitates and secondary defects in the various nucleations aspects and growths for implanted wafers. The As doping profiles by spreading resistance profilometer were also examined.

The germano-silicate glass, which is defect-free and hydrogen-loaded, is photosensitive to 248 nm light. The photosensitivity is shown to require the presence of hydrogen. Four types of germano-silicate glass were examined. The oxygen-deficient defects increased the photosensitivity of germano-silicate glass to light supporting a wavelength of 248 nm in hydrogen-free and hydrogen-loaded cases.

Ion energy distributions, relative ion intensities and absolute total ion current densities were examined at the grounded electrode of an inductively coupled Gaseous Electronics Conference radio-frequency reference cell for discharges produced in pure argon, nitrogen, oxygen and chlorine, and in mixtures of argon with N2, O2 and Cl2. Measured current densities were substantially greater for pure argon and for mixtures containing argon than for pure N2, O2 and Cl2.

Research was conducted to examine the propagation of ruthenium and oxygen atoms in vacuum and in an oxygen ambient by means of observing the fluorescence from excited atoms in the plume using a framing streak camera. The focusing depth of the camera was taken into consideration in the analysis of the plume spatial distribution. Results indicate that the spatial distributions of O and Ru atoms were shifted Maxwellians in vacuum.

Research was conducted to examine a model for the growth and dissolution of oxygen precipitates in Czochralski silicon during heat treatment. Newly derived growth and dissolution rates were inserted into a set of chemical rate equations and a Fokker-Planck equation. A comparison of the simulated results with experimental ones reveal that the model is useful for calculating the depth profile and the defect densities under inert conditions and oxidation conditions.

The effect of 90 high energy (MeV) oxygen ion induced disorder on the magnetotransport in epitaxial La0.7Ca0.3MnO3 (LCMO) thin films was investigated. Epitaxial films of LCMO were subjected to irradiation with 90 MeV oxygen ions at different dose values. The magnetization, structural and magnetotransport characteristics were analyzed as a function of the ion dose. Experimental results showed that there is swelling in the surface morphology of the LCMO thin films probably caused by subsurface clustering of point defects.

A study was conducted to examine the effects of oxygen on the thermal stability of amorphous hydrogenated carbon films by annealing them at 520, 610, and 670 K in vacuum and in O2 flow. The films were deposited by microwave plasma from a solution of 10 sccm pure methane and 100 sccm hydrogen in an electron cyclotron resonance chemical vapor deposition system. Results indicated that the transformation for annealed samples in O2 gas flow is supported at low temperatures.

The negative ion density in high-density and low-pressure oxygen plasmas was measured with the aid of probe-assisted laser photodetachment. Plasmas were produced in a vacuum vessel containing a quartz discharge tube, a cylindrical stainless-steel chamber and a rectangular stainless-steel chamber. Results showed an efficient generation of negative ions caused by dissociative electron attachment to metastable molecular states.

Mixed Group V ternary alloy GaAs1-yPy(y

A study of the physical changes of As-grown Czochralski silicon samples subjected to different temperatures reveals that loss of oxygen at low temperatures obeys second-order kinetics. The samples used have different oxygen concentrations. The loss of oxygen according to second-order kinetics is explained by the diffusivity of oxygen, which is larger than the normal rate of diffusivity by a factor of 3.

Experimental analysis of the effects of annealing on Si SiO2 Si structures shows that annealing induces oxide degradation, oxygen gettering and two oxygen-vacancy-related defect centers in the structures. Negative and positive charge traps develop during annealing while the O interstitial concentration rises with respect to the anneal temperature. The solubility limit of the O interstitial mediates the oxygen gettering process.f

Analysis of the annealing behavior of carbon-oxygen complexes that cause peaks at 1108 cm-1 and at 1104 cm-1 in silicon crystals using infrared-absorption method reveals that concentrations of both the carbon-oxygen complexes reach quasithermal-equilibrium values due to annealing. The quasithermal-equilibrium concentration increases with an increase in the temperature for annealing temperature exceeding 800 degrees Celsius. The effects of annealing follow a mass-action law that indicates that the two complexes contain an oxygen atom and a carbon atom.

An experimental study of the desorption of sputtered carbon films to examine whether tribochemical processes activate the desorption reaction shows that tribochemical wear process induces desorption of carbon films to CO2 and CO surface oxides. The production of carbon dioxide during sliding in dry-oxygen and -nitrogen environments supports the tribochemical wear-induced desorption. The tribochemical wear model helps develop a sampling system and pressure interface for experiments.

Radio frequency phase difference is used as a standard for the determination of the influence of optical emission intensities (OEIs) of oxygen or argon radicals and ions in the O2 supermagnetron plasma. The plasma is embedded during lower cathode radio frequency (LORF) power and upper cathode power radio frequency (UPRF) oscillations. An increase in CORF and the UPRF increases OEIs. The O2 super plasma etches the photoresist, which produces the optical omissions.

Atomic oxygen generated by a direct current glow-discharge is studied when it permeates through a Ag0.05Zr membrane over a temperature of 650 degrees celsius. The data obtained is compared to the molecular oxygen's ordinary permeation. Results show that surface concentration of oxygen atoms is more than the solubility limit of normal thermal dissociative permeation at low temperatures and glow-discharge conditions. Flux in this glow-discharge condition is large due to very high concentration gradient.

Optically excited surface plasmons facilitate the detection of photochromic effect of thin amorphous WO3 films. Bleaching and coloration processes are influenced by oxygen, and during photochromic process, there is an oxygen exchange between the ambient atmosphere and the sample. Under N2, O2, Ar, He and vacuum conditions, coloration-bleaching tests reveal the effect of ambient atmosphere on photochromic behavior.

The steady-state electron energy distribution function (EEDF) in oxygen and chlorine gases under direct current and alternating current fields was studied. A finite element code was employed to solve the spatially uniform time-dependent Boltzmann equation that describes the EEDF in various gas discharges. Results that the proposed quasi-steady-state approximation is capable of signicantly reducing the computation time required for the analysis of gas discharges.

The influence of atomic hydrogen and oxygen on diamond growth was investigated using high-resolution energy loss spectroscopy. The results showed that in the case of a totally desorbed diamond surface, atomic hydrogen had a corrosive effect initially on carbon atoms on the surface then subsequently on the dangling bonds of sp3 hybridized atoms on the next layer of diamond surface.

The effect of oxygen introduction on secondary ion mass spectrometry imaging of Pt/Si structures was investigated. The results showed that oxygen caused profile disturbances in the interface region. The extent of these profile disturbances were determined by the oxygen pressure. The segregation brought about by field-induced migration was heavily dependent on oxidizing conditions.

The influence of oxygen on the electronic and optical characteristics of AlInAs layers lattice matched to InP substrates grown by metalorganic chemical vapor deposition was investigated using secondary ion mass spectroscopy. The results showed that residual oxygen concentration was high when the growth temperature was low. Both the oxygen concentration and the residual concentration exhibited a similar dependence on the V/III ratio, indicating that residual carrier concentration originated with oxygen.

The influence of oxygen exposure, polymer porosity, interface and bulk trapping on the stability of the inversion layer in a polymer field effect transistor structure was investigated using a model. The model indicated that initial decay was dependent on the ratio of the decay to the surface traps. When oxygen was not present, the stability of the device wasenhanced by consecutive chargings.

The behavior and diffusion characteristics of oxygen in liquid Ag-Yb1Ba2Cu3 and Tl1Ba2Ca2Cu3 alloys were investigated using a modified coulometric titration technique. The results showed that the growth mechanism was not affected by the additional incorporation of Ag but oxygen diffusion actively controlled the film growth process. Enhanced oxygen solubility caused the film growth rate to increase. The Tl1Ba2Ca2Cu3 alloy exhibited high oxygen solubility at 900 degrees celsius.

The structural characteristics of interstitial oxygen absorption bands in Si at low temperaturres were investigated using the molecular orbit theory. The results showed that there was a correlation between band splitting and the energy transitions. In addition, there was a close association between the local Si-O-Si bond and the six silicon atoms with S6 symmetry nearest to it. As the temperature was decreased, absorption peaks became narrower and higher.

The precipitation of oxygen in 2 MeV electron irradiated silicon samples was investigated using transmission electron microscopy. The results showed that the samples initially featured varying vacancy-oxygen concentrations created by irradiation or a vacancy-dioxygen center created by annealing at 350 degrees celsius after irradiation. In addition, enhanced precipitation was observed in the vacancy-oxygen samples.

The influence of oxygen on the electroluminescent properties of ZnS:TbOF and ZnS:TmOF devices were investigated. The results showed that increased oxygen deposition temperatures resulted in an increase in the luminance and the luminescent decay time. The threshold voltage decreased in ZnS:TbOF devices but did not change in ZnS:TmOF devices. Improvements in the film uniformity and grain size were obtained by deposition in an oxygen atmosphere.

Interstitial oxygen reduction in silicon wafers with a range of initial oxygen and carbon concentration annealed at 450, 475 and 500 degrees celsius were investigated. The results showed that the oxygen loss rate scaled at the fifth power of oxygen concentration for the silicon wafers annealed below 500 degrees celsius.The emission of silicon interstitials accompanied the formation of large clusters. Higher temperatures and larger carbon concentrations effectively reduced the strain barrier and allowed the formation of stable O3 clusters.

The behavior of interstitial oxygen during epitaxial silicon growth on Czochralski crystal substrates was investigated using high-resolution Fourier transform infrared spectroscopy. The results showed that oxygen contamination of the epilayer occured due to solid-state outdiffusion from the substrate during the deposition process. Oxygen contamination was associated with the dopant type present in the substrate.

Reactive ion etching of InP using a C2H6/H2/O2 mixture was investigated. In addition, the effects of O2 addition to the C2H6/H2 gas was studied. The results showed that the addition of oxygen gas to the base mixture produced an extremely smooth etched surface. The oxygen gas significantly decreased hydrocarbon polymer formation during the etching process and reduced the roughness of the etched surface.

The parasitic effects of oxygen on the thermoelectric characteristics of Si80Ge20 doped with Ga and P were investigated. The results showed that alloys which contained oxygen levels higher than 2.0 at.% featured low carrier mobilities and low thermal conductivities. Alloys which contained oxygen levels lower than 0.6 at. % exhibited high carrier mobilities and high thermal conductivities.

The effect of oxygen on the electrical and optical characteristics of GaN crystals grown by metalorganic vapor phase epitaxy was investigated using Van der Pauw-Hall measurements, optical absorption spectroscopy and photoluminescxence measurements. The results showed that the presence of oxygen in the GaN grown layers resulted in increased carrier concentration and altered compensation behavior in Zn.

The effect of oxygen on diamond synthesis in a microwave plasma jet is investigated. The ratio of hydrocarbons to hydrogen in a source gas and that of CHx to C2H2 was found to be important in diamond synthesis. Oxygen removes C2H2 selectively in a boundary layer by producing carbon monoxide. This process suggests that oxygen forms an advantageous environment for diamond synthesis rather than accelerate the removal of nondiamond carbons.

The magnetic properties and also the domain structure in CoFe2O4 thin films epitaxially grown on MgO substrate are investigated. Due to large magnetostriction and the mismatch existing between the lattice and MgO, it was seen that other sources of anisotropy such as stress prevailed and it competed with magnetocrystalline anisotropy in CoFe2O4 films.

The magnetic frustration effects in the La(sub 1-x)Ca(sub x)MnO3 (x=0.2,0.3) single crystals from dc and ac susceptibility measurements are investigated. It was seen that the magnetic transition around 100 K involving probably charge-ordered phase was affected by the frequency and the spin dynamics of La(sub 0.8)Ca(sub 0,2)MnO3 that changed drastically at high frequencies (approximately at 10 KHz).

(001) substrate as a function of film thickness (50 and 100 nm) and oxygen content (optimum and reduced) is investigated using magnetic force microscopy. The domain nucleation and growth takes place by discrete reorientation of regions that have diameters similar to the final domain width.

The systematic electron-spin resonance (ESR) investigation on polycrystalline Nd(sub 1-x)Sr(sub x)MnO3 (x=0.3, 0.33, 0.4 and 0.5) in the temperature range of 100-400 K is reported. At a characteristic temperature T(sub star), which is above the magnetic transition temperature T(sub c), the line splits into two magnetically ordered phase, indicating the existence of two types of phase-segregated regions.