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Atmospheric lidar techniques for the measurement of wind, temperature, and optical properties of aerosols rely on the exact knowledge of the spectral line shape of the scattered laser light on molecules. We report on spontaneous Rayleigh-Brillouin scattering measurements in the ultraviolet at a scattering angle of 90[degrees] on [N.sub.2] and on dry and moist air. The measured line shapes are compared to the Tenti $6 model, which is shown to describe the scattering line shapes in air at atmospheric pressures with small bur significant deviations. We demonstrate that the line profiles of [N.sub.2] and air under equal pressure and temperature conditions differ significantly, and that this difference can be described by the $6 model. Moreover, we show that even a high water vapor content in air up to a volume fraction of 3.6 vol.% has no influence on the line shape of the scattered light. The results are of relevance for the future spaceborne lidars on ADM-Aeolus (Atmospheric Dynamics Mission) and EarthCARE (Earth Clouds, Aerosols, and Radiation Explorer). OCIS codes: 280.3640, 280.1310, 290.5830, 300.6390.

We report precision measurements of the refractive indices of dry air, [N.sub.2,] [O.sub.2,] Ar, and C[O.sub.2,] performed by using a frequency comb as the light source in a Mach-Zehnder interferometer setup. Improved dispersion formulas for all gases are derived with a sensitivity level of 10-9. These results are valid for a wavelength range from 740 to 860 nm and are in good agreement with measurements from other groups. OCIS codes: 120.3180, 120.3940, 120.4530.

Propagation of a dye laser beam of wavelength 5700 A through nitrogen is considered. Values of transmittance, averaged over intervals of 0.5 [cm.sup.-1], are obtained for absorber thicknesses of 0.1, 1, and 10 atm-cm, using the quasi-random model of molecular band absorption. From these values, intensities of the absorption lines in the first positive system of [N.sub.2] are simulated in the frequency interval of 17,540-17,548 [cm.sup.1]. OCIS codes: 010.1290, 010.1300, 010.1320, 010.3310.

The measurements are carried out for laser parameters in a transversely excited [N.sub.2] laser with a variable electrode gap separation by using an arrangement based on an oscillator-amplifier laser (OSC-AMP) system. The results have shown that laser parameters are following characteristic curves and the obtained curves that relate these parameters to the AMP gap separation are presented.

The direct Monte Carlo method (DMCM) is used to study enhancements in rates of ionization, dissociation and current in the dc saddle field (DCSF) glow discharge. It is observed that the DCSF operates at low pressures with efficiency, which makes it attractive for the production of thin films whose qualities are sensitive to gas phase reactions.

The stress dependence of the room-temperature cathodoluminescence (CL) spectrum of N-doped cubic silicon carbide is analyzed in a field-emission-gun scanning electron microscope by using the electron beam as an excitation source for luminescence emission. The results have stated that the stress assessment technique is available in conventional scanning electron microscopy (SEM) devices coupled with CL spectrometers for the nondestructive evaluation of residual stresses in N-doped 3C-SiC-based devices.

The spatial distributions of the intensity of fluorescent light emitted from neon and nitrogen excited with 12 keV electron beams at gas pressures from 250 to 1400 hPa are measured. The CASINO program, which performs Monte Carlo simulations of electron scattering, has offered a simple and relatively precise method to predict the spatial distribution of the light emitting species created by low energy electron beams in dense gas.

The dissolution of a dislocation loop layer under the influence of inert Si[O.sub.2]/Si and nitrogen-rich Si[O.sub.2]/Si interfaces is studied. The results have shown that during the nonconservative Ostwald ripening process the defect band loses interstitials mainly due to the dissolution of perfect prismatic loops, while Frank loops remain almost unaffected by the presence of both interfaces.

The application of recently developed diffraction theory for continuous wave photothermal deflection (PD) spectroscopy in the measurement of the temperature coefficient of the refractive index, dn/dT, of a gas as a deflecting medium is described. The values of thermal diffusivity [alpha.sub.g] and dn/dT changing with concentration is explained by using thermodynamic theory and Lorentz-Lorenz formula, respectively.

The optical phonon frequencies of the wurtzite semiconductors GaN and ZnO are calculated as a function of angular variation with respect to the c-axis of these wurtzite crystals. In this article, it is shown that the interface phonon interaction potentials dominate the phonon interactions in both the heterostructures when the dimensions of the structures are small enough.

The spontaneous emission mechanisms in stain-free Al (sub x) Gad (sub 1-x) N films were studied in this article. The results showed that they exhibited a band-gap bowing with a parameter of approximately minus 0.82 eV.

The study concerns the analysis by x-ray diffraction (XRD) of residual stresses in fiber-textured TiN thin films grown by sputter deposition. The results suggest that the strain is not the dominant factor in controlling the development of preferred orientation in these films, the governing process being rather competitive growth.

The absolute value of the efficiency of electron injection from an excited coumarin dye (NKX-2311) into a nanocrystalline ZnO film was estimated through transient absorption measurements. The electron injection process can also be quantitatively analyzed by comparing their efficiencies.

Essential mechanistic aspects of NO/H2/O2 reaction at 140 degree C were studied using mass spectroscopy and DRIFTS. Inactive adsorb NO(sub x) species (spectators) were found to accumulate on both Pt and support surfaces.

The properties of nitrogen-doped fluorinated silicon oxide (SiOF) films deposited on silicon is analyzed using hydrosilicofluoric acid and ammonium hydroxide aqua as sources by the temperature-difference-based liquid-phase deposition (TD-LPD) method. It is concluded that nitrogen-doped SiOF films by the TD-LPD method with NH4OH incorporation is suitable for intermetal dielectric application.

Positron annihilation lifetime spectroscopy (PAS) and nitrogen gas adsorption method (BET) is used to study a number of silica supported nickel carbonate systems and to evaluate the pore size distribution in the samples. It was found that ortho-Positronium (o-Ps) represents the pores of smaller size in a sample with wide pore size distribution.

The frequencies of several new platinum nitride species produced by the reaction of laser-ablated platinum with pure nitrogen is calculated with the density functional theory in addition to the complexes observed in earlier thermal atom studies. Results revealed that absorptions are observed for PtxNN, PtNN(super -), Pt(NN)(sub 2)(super -) and Pt(NN)2 in solid argon and neon.

R-matrix calculations for neutral (N I) and singly ionized nitrogen (N II) have been undertaken in the energy region below 50 eV and 180 eV. Spectroscopic measurements were performed in the visible and vacuum-ultraviolent spectral range. Electron densities from 1.8 to 7.0x10(super13) cm(super-3) were obtained from plasma diagnostics, and the rate coefficients were obtained from absolute level densities.

This paper demonstrates our optical measurement system based on near-infrared tunable diode laser absorption spectrometry and reports the results of trace moisture determination in nitrogen and ammonia gases. A near-infrared InGaAsP distributed feedback diode laser operating at room temperature was employed as the optical source. We used a dual-cell detection strategy to cancel common mode noise from the diode laser and remove the effect of the residual moisture absorption in the beam path outside the sample cell. We also used this method to successfully eliminate the interfering absorption of matrix gas molecules such as N[H.sub.3]. The detection limit of [H.sub.2]O absorption of 4 ppb in nitrogen and 12 ppb in ammonia was obtained using a single-pass absorption cell of only 92 cm in length and the average results of 10 scan measurements. This system has characteristics of both the high sensitivity and capability of in situ and real-time measurement.

The annealing properties, structural damage formation and recrystallization of nitrogen-implanted n-type III-V compound semiconductor InP were investigated. Commercially prepared n-type (100) InP samples doped with sulphur were implanted at room temperature using a 100-kV isotope separator. Results showed that implantation dose influenced the depth of an amorphous layer as well as the type of the vacancy defects. Annealing temperature also affected the type of the vacancy defects.

The accuracy of temperature and simultaneous relative [N.sub.2]-[O.sub.2] concentration measurements of accumulated as well as of single-pulse rotational coherent anti-Stokes Raman spectra has been investigated in air in the temperature range from 300 to 2050 K. The experimental spectra were taken in a high-temperature oven at atmospheric pressure for a constant oxygen concentration of 20.9% (air). The evaluation procedure is based on the energy-corrected sudden-power scaling law. The agreement of the thermocouple readings with the mean values of the evaluated coherent anti-Stokes Raman spectroscopy temperatures is higher than 50 K and independent of the temperature. The evaluated oxygen concentration is found to be in the range from 20.0 to 21.7% and is also independent of the temperature.

Electrical and optical activity of boron incorporated in p-type 4H- SiC layers was observed. Under cathodoluminescence (CL) excitation, efficiency of deep boron related luminescence in compensated material depends on the concentration of attendant impurities (Al, N) and the concentration ratio of AI to N atoms.

Several diagnostic approaches are employed to explain the mechanisms involved in the propagation of the spark-generated shockwaves taking place in the argon glow discharges and afterglows. The electrons with temperature greater than the room temperature are shown to get highly compressed at the shock front.

The evolution of both the density of states (DOS) located between the band-tail states and the DOS around the Fermi level in amorphous carbon nitride films as a function of the total nitrogen partial pressure ratio in the Ar/[N.sub.2] plasma mixture is discussed. The changes in the optoelectronic properties are attributed to the modification in the atomic bonding structures and the electrical conductivity variation is interpreted in terms of local effects on the nature and energy distribution of [pi] states.

Ion focusing in enhanced glow discharge plasma immersion ion implantation (EGD-PIII) of hydrogen into silicon has affected the lateral ion fluence uniformity and the phenomenon and its effects are examined and compared to those in nitrogen EGD-PIII. The impact of the negative high voltage on the ion focusing effect is small when compared to that of the plasma density.

The spectroscopic ellipsometry technique is employed to explain the different optical properties of the nanostructured silicon quantum dots present in the Si/Si[N.sub.x] films. These properties are shown to be completely dependent on the flow of ammonia in the films.

The heteroepitaxy of a-plane (1120) InN films on r-plane (1102) sapphire substrates, by nitrogen radio frequency plasma-assisted molecular beam epitaxy, is examined and compared to that of c-plane (0001) InN. The epitaxial growth of a-plane InN has proceeded through the nucleation, growth and coalescence of three-dimensional islands, which has resulted in surface roughness that has increased monotonically with epilayer thickness.

A cold He plasma jet generated by a single plasma electrode jet device is analyzed and the spatial-temporal resolved optical emission spectroscopy measurements are described. The studies have shown that the Penning effect between the metastable state [He.sub.m] and the air molecules have played a major role in the propagation of the plasma bullet in the open air.

A monitoring probe is developed for atomic radicals by using the vacuum ultraviolet spectroscopy (VUVAS) with the microdischarge hollow cathode lamp (MHCL). The spatial distribution of the absolute densities of H and O atomic radicals in a radical-based plasma processing system is measured by moving the probe along the radical direction of the chamber.

High-resolution cathodoluminescence experiment is used for studying the effect of nitrogen doping on the exciton and nitrogen-vacancy (NV) defect states in a homoepitaxial chemical vapor deposited (CVD) diamond thin film. The results have shown that the exciton and nitrogen-related defect emission spectra underwent a shift of the peak position to a longer wavelength by nitrogen doping.

The effect of the radio frequency power supply on the particle presence within the plasma is analyzed, were the particles are generated in low pressure radio frequency C[H.sub.4]/[N.sub.2] discharges containing nitrogen. The results have helped in understanding the power influence on the particle growth within the plasma.

The [N.sub.2]-induced quenching of He-induced intensity enhancement effect is studied in reduced-pressure plasma emission produced by Nd-YAG irradiation on solid zircaloy and porous fossil samples. The quenching effect is explained as a consequence of energy depletion of the He metastable excited state triggered by the Penning ionization process induced by the presence of nitrogen.

The effect of the nitrogen concentration on the growth and the photoluminescence (PL) spectra of the silicon nanocrystals (Si-ncs) are examined. The results have shown that a relatively low nitrogen atomic fraction has increased the PL emission, whereas the PL intensity is decreased as the large nitrogen concentration prevents the formation of Si-nc.

The interaction of low-energy nitrogen ions with GaAs (100) surfaces by photoemission spectroscopy (PES) around N 1s and Ga 3d core levels and near-edge x-ray absorption fine structure (NEXAFS) around the N K edge is studied. Nitrogen interstitials and antisites are identified in NEXAFS spectra, while interstitial molecular nitrogen has provided a clear signature in both PES and NEXAFS.

The optical and electrical properties of N-doped ZnO thin films, grown by plasma-assisted molecular beam epitaxy, with different doping concentrations are examined. The results have shown that highly doped samples are heavily compensated and the donor-acceptor pair (DAP) emission band has displayed a strong redshift and broadening with increasing nitrogen doping concentration.

The strain and defect state of silicon implanted with nitrogen by plasma immersion ion implantation is examined using various spectroscopy methods. The close relationship between the calculated strain profiles and Auger electron spectroscopy (AES) nitrogen concentration profiles outside the amorphous regional signal has indicated interstitial nitrogen as the main source of strain.

Density functional theory is used to study the structural, electronic and optical properties of oxygen-defective [Zn.sub.3][N.sub.2]. The results have shown that [Zn.sub.3][N.sub.2] with nitrogen replaced by oxygen is more stable than that with interstitial oxygen and substitutional oxygen for nitrogen in defective [Zn.sub.3][N.sub.2] is responsible for the n-type conduction character.

A method of gas temperature determination, which employs fits of numerically generated spectra of the bands of the first positive system ([B.sup.3]][PI.sub.g]->[A.sup.3][SIGMA.sup.+.sub.u]) of nitrogen is described. Gas temperature values inferred by this method and by using the 3-0 band peak ratio method show good agreement for helicon plasma.

A combination of ultraviolet-visible absorption spectroscopy and first-principles density-functional calculations is used to investigate the optical-response properties of nitrogen(N)-doped titanium dioxide (Ti[O.sub.2]) films. The reproducible and controllable photoabsorption behavior of the N-doped Ti[O.sub.2] films is obtained by controlling the ion dose under certain conditions.

The chainlike silicon nanowires SiNWs are synthesized by fluctuating the pressure of the carrier gas in the growth process. The X-ray excited optical luminescence and photoluminiscence spectroscopy show that the relatively strong luminescence from the chainlike SiNWs compared to normal SiNWs arises mainly from silicon oxide in the chainlike SiNWs.

Defect size distributions in nitrogen-doped Czochralski (N-CZ) silicon wafers are obtained using an oxygen precipitate profiler and Wright-Jenkins etching. The findings show that the depth dependent defect concentration correlates well with oxygen and strongly with nitrogen secondary ion mass spectroscopy profiles, suggesting that nitrogen is the leading impurity in the defect formation processes even though introduced at very low concentration.

Nitrogen segregation and coprecipitation with oxygen in N-doped Czochralski (N-CZ) silicon wafers are investigated as a function of depth based on extended defect structure and chemical composition. The precipitate atomic and microstructures, analyzed by high resolution TEM and scanning transmission electron microscope (STEM) demonstrate that second phase precipitate is precursor to a third phase that is an outer oxynitride shell.

The Spectroscopic ellipsometry (SE) is used to study the optical properties of N+ ion-implanted Si(100) wafer. The SE data reveal that the recrystallization starts to occur very quickly and the time constant for the defect annealing in the deeper damaged layer is determined to be 36 s.

Temperature-dependent reflection measurements are carried out on InN thin films to determine its refractive index n and its temperature coefficient dn/ dT. The findings show that various growth conditions, especially the substrate temperature, yields in InN thin films with different optical band gaps, resulting in large fluctuation of the dn/dT near the optical band gap.

Photoreflectance investigations of the energy-fine structure of GaInNAs/GaAs multiple quantum wells (MQWs) grown at different temperatures and postgrown treated by rapid thermal annealing (RTA) is reported. A 'splitting' of the ground and excited QW transitions due to the presence of different nitrogen nearest-neighbor environments was observed.