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Experiments have verified that it is possible to customize the magnetic behavior of sputtered magnetostrictive [([Fe.sub.80][Co.sub.20]).sub.80][B.sub.20] by controlling the stress induced in the deposition. It is shown that the mechanical stresses accumulated during deposition are important factors for controlling coercivity.

The sandwiched structures with layer of amorphous silicon (a-Si) between two a-SiN layers are fabricated by plasma enhanced chemical vapor deposition technique. The study concludes that the discrete quantum energy levels, rather than the interface state, are the dominating cause of charge trapping and storage in the structures.

A phenomenological model of photoluminescence yield an decay times of proton irradiated and thermally annealed amorphous hydrogenated silicon carbon alloys is presented.

Hard disk amorphous carbon coatings were studied to observe tribocharging phenomena.

Epitaxial and amorphous films of Gd2O3 and Y2O3 were studied to determine materials growth and properties.

A new study uses scanning tunneling spectroscopy to investigate the surface topography of amorphous nitrogenated carbon films deposited using a filtered cathodic vacuum and a Kaufman-type ion source.

The excimer laser fluence used in crystallization was modulated by a beam mask to determine the link between excimer laser fluence gradient and length of lateral grain growth in amorphous silicon films.

Amorphous diamond-like and carbon nitride films deposited by pulsed laser deposition were studied.

Thermal annealing and its effects on ta-C films is examined.

A new study investigates the optical characteristics of hydrogenated amorphous and polymorphous silicon films deposited on glass.

A new study investigates the influence of limited instrumental bandwidth on the accuracy of methods uses to determine the density of states from modulated photoconductivity and transient photoconductivity data.

A new study investigates the properties of thin p-type microcrystalline silicon films prepared on boron-doped amorphous silicon carbide.

A new study uses the agglomeration and partial oxidation of thin amorphous Si0.7Ge0.3 layer deposited on SiO2 to make nanocrystals with a high spatial density and small size.

A new study investigates limitations to the recombination mechanisms in amorphous silicon/crystalline silicon heterojunction solar cells.

A new study investigates the origins of the current gain sometimes exhibited in amorphous silicon n-i-p-i-n structures.

A new quantitative study investigates the Hall effect in amorphous TbxCo1-x thin films.

A new study extends the examination of H bonding in hot wire chemical vapor deposition techniques, focusing on hydrogenated amorphous silicon and using x-ray diffraction and infrared spectroscopy.

Research demonstrates a strong pixel dwell-time constraints in the formation of cobalt disilicide layer using focused ion beam implantation of cobalt into silicon. Data show that because of the damage build-up during implantation, short dwell times in the range of microsecond are used.

Results describe production of amorphous zones by the direct impact of energetic heavy ions in GaAs at 30 and below 300 K as the process is affected by recrystallization above 250 K. Data also show that damage analysis is better conducted at the implantation temperature.

Amorphous hydrogen-free carbon films were subjected to focused ion beam.

Deposited films with a low paramagnetic defect density have been grown to meet the need for hydrogenated amorphous carbon thin films that allow n-type electronic doping by nitrogenation.

A new study uses micro-Raman spectroscopic analysis to investigate the structure of tetrahedral amorphous carbon films deposited under a variety of conditions.

The effects of ultraviolet light irradiation and thermal annealing on the photoluminescence (PL) of hydrogenated amorphous carbon nitride thin films have been studied. The films were fabricated through electron cyclotron resonance plasma using various mixtures of N2 and CH4 gases. Results indicate that the PL peak energy does not depend on nitrogen but the intensity decreases as nitrogen content increases. The intensity diminishes with the redshift of the spectrum as the annealing temperature increases and is completely quenched as the annealing temperature rises beyond 400 C.

The thermal and absorption effects of laser illumination on the stability of amorphous multilayers (AMLs) have been studied by measuring the Raman spectra of Se/Se(sub 100-x)Tex multilayers at room temperature and at 38 K. Results indicate that the crystallization temperature of Se70Te30 sublayers and the AML stability increase with decreasing sublayer thickness. It was also observed that the crystallization temperature of the Se sublayers is dependent on the Te content of the Se(sub 100-x)Tex sublayer.

Research was conducted to examine the growth, microstructure and electronic properties of amorphous carbon nitride films (a-CN(sub x)) via plasma diagnostics. The objective was to correlate the variation in the structure, properties and growth rate of a-CN(sub x):H films with the relative concentrations of different radicals present in electron cyclotron resonance-radio frequency plasma as a function of nitrogen concentration.A proposed model that describes film growth and nitrogen incorporation in the films is presented.

Research was conducted to examine amorphous (Nd0.38Fe0.62)(sub 1-x)B(sub x) samples aimed at increasing the negative effective anisotropy into the range of positive values, that is, easy axis perpendicular to the film plane. Results indicate that the addition of boron to the amorphous Nd Fe matrix reduces the magnetization, enhances the effective perpendicular anisotropy and enhances the Kerr rotation angle.

Research was conducted to examine the amorphous carbon-germanium films (a-Ge(sub X)C(sub Y):H) produced by plasma-assisted chemical vapor deposition from tetramethylgermanium in a radio-frequency glow discharge. Results indicate that the internal photoemission is a very useful tool to determine basic parameters of the electronic structure of thin insulating film. Findings also demonstrate that the insulating a-Ge(sub X)C(sub Y):H films do not reveal practically any bulk photoconductivity for the photon energies lower than the transport gap E(sub G).

Research was conducted to determine the measurements and to analyze amorphous carbon (a-C) films grown n-type Si(100) substrates by rf magnetron sputtering. The objective was to investigate the effect of the construction of thin films on the electrical properties of the bulk and the interface. Results indicate that the construction of the a-C films and the presence of layered and bilayer structures influence the characteristics of the device.

A study was conducted to investigate the microstructure, magnetic properties and giant magnetoimpendance (GMI) of nanocrystalline soft magnetic Fe(sub 92-x)ZrBxCu1 ribbons when their iron content is replaced with boron. Experimental results show that the thermal stability of the ribbons' amorphous precursor is improved while their body-centered cubic phase grains are reduced in size as the born content increases. A correlation between the ribbons' magnetic properties and GMI was also noted

The pseudodielectric-function spectra of the bulk amorphous-like semiconductor, a-ZnIn2Te4, are measured through spectroscopic ellipsometry in the 1.2-5.3 eV photon-energy range at room temperature. Results show similarity between the measured spectra and the amorphous tetrahedrally bonded semiconductors. Complex refractive index, normal-incidence reflectivity and absorption coefficient of a-ZnIn2Te4 are also described.

Research was conducted to examine the magnetic properties of Fe and Ni based on the theory of metallic magnetism which interpolates between amorphous and crystal structures via the average coordination number and the interatomic distance fluctuation. Results demonstrate that the nonunique experimental data can be explained using the different degrees of structural disorder. It is concluded that the different degrees of structural disorder yield different values of critical temperature and the magnetization.

Research was conducted to examine the plasma deposition of low-dielectric-constant fluorinated amorphous carbon. The objective was to investigate the feasibility of adjusting the fluorine-to-carbon ratio by changing the deposition pressure to improve thermal stability. Results indicate a tradeoff relationship between a low dielectric constant and high thermal stability and the tradeoff could be optimized by the pressure during deposition.

Electron energy loss spectroscopy studies of the amorphous to crystalline transition in FeF3 were conducted. The time-resolved studies reveal that the coordination polyhedra in amorphous FeF3 were randomly arranged FeF6 octahedra which are retained in amorphous FeF3. The change in the d-band occupancy by one electron and the sensitivity of the ratio of Fe L3 and L2 edges to the charge state of the iron ion are clearly illustrated using electron energy loss spectroscopy.

Research was conducted to examine the preparation of amorphous carbon (a-C:F) thin films with low fluorine concentration, low hydrogen concentration and low dielectric constant using magnetron sputtering with hydrogen gas dilution in CF4 gas. Infrared absorption, x-ray photoelectron spectroscopy, electron spin resonance and ultraviolet visual spectroscopy were used to study the structural, optical and defect properties of the thin films. Results are consistent with the result that no change in the dielectric constant after annealing at 300 degrees C was observed for the a-C:F film with a fluorine concentration of approximately 50 at.%.

Research was conducted to examine the preparation of amorphous CN(sub x) thin films by pulsed laser deposition (PLD) using a radio frequency radical beam source. A graphite target that utilized a nitrogen radical beam source during the deposition process was used. The effects of nitrogen pressure in the PLD chamber and radio frequency input power were also examined. To characterize the deposited films, Fourier transform infrared and Raman scattering spectroscopy were used.

Research was conducted to examine the optical luminescence of amorphous SiO2 over a wide dose range, from 0 up to 400 Mrad volume average dose. X rays stimulated the luminescence and the x radioluminescence was measured continuously as the dose accumulates in the sample. Results demonstrate that the x radioluminescence method offers a convenient way to study the dose dependence of different spectral regions under identical experimental conditions.

Research was conducted to examine the evolutions of the uniaxial torque and magnetization with the applied magnetic field which permits a discrimination of the sources of in-plane magnetic anisotropy in amorphous ribbons. A simple model was developed for an inhomogeneous material to determine the magnetic anisotropy sources. The model was applied to explain the different behavior seen in the evolution of the uniaxial torque amplitude with the applied magnetic field of two commercial Co-based amorphous alloys.

Research was conducted to examine the kinetics of hydrogen incorporation in amorphous silicon films. The hydrogen concentration incorporated in the Si films deposited by low pressure chemical vapor deposition using phosphine and disilane was investigated using nuclear resonant reaction analysis. Results are in good agreement with previously reported values derived via surface analysis and desorption analysis.

Research was conducted to examine the pseudodielectric-function spectra of amorphous selenium (a-Se) in the 1.2-5.2 eV photon-energy ranged calculated by spectroscopic ellipsometry at room temperature. The measured spectroscopic ellipsometry data were analyzed based o the Jellison-Modine model. An analysis of the dielectric-related data, such as the complex refractive index, absorption coefficient and normal-incidence reflectivity, of a-Se was also performed.

Research was conducted to examine the optical excitation of Er3+ ions in amorphous silicon-nitrogen thin film (a-SiN) alloys. The (super 4)I(sub13/2) -> (super 4)I(sub 15/2) transition from Er-doped a-SiN thin film alloys was studied by photoluminescence excitation spectroscopy. Results indicate that the Er3+ ions can be excited either by host carrier-mediated processes, or directly through intra-4f Er3+ levels.

A study on hydrogenated amorphous silicon-based thin film transistors presents noise measurements of alpha-Si:H thin film transistors with an inverted, staggered structure. Noise was measured when the device operated in the conducting mode. It was found that the 1/f noise dominates at low frequencies. This noise also originates from different physical locations based on whether the thin film transistor operates in the linear or the saturation regime.

A study on techniques to develop polycrystalline silicon-based thin-film transistors for higher-performance, active-matrix, liquid-crystal displays investigated the laser crystallization of hydrogenated amorphous silicon thin films grown on glass substrates using plasma-enhanced, chemical-vapor deposition. The structure of the resulting polycrystalline silicon films was investigated using atomic force microscopy and transmission electron microscopy. Results are discussed.

Research was conducted to examine the effects of ion implantation and thermal annealing upon the photoluminescence (PL) observed in amorphous silicon nitride films prepared by the low-pressure chemical vapor deposition method. An increase of the implanted dose of Ar+ ions leads to a decrease in PL intensity and a shift to lower energy of the PL peak energy. Results reveal that the defects generated by hydrogen release or bond breaking serve as nonradiative recombination centers that quench the PL.

A study presents the results of measurements of the temperature dependence (100-700 K) of Seebeck coefficient and electrical resistivity of the ternary chalcogenide GeBi4Te7 with different deviation from stoichiometry together with room temperature Hall concentration and mobility data. Results of the study demonstrate that the transport properties of GeBi4Te7 strongly depend on deviations from stoichiometry. Other experimental findings are discussed.

A study was conducted on the removal of secondary or end-of-range (EOR) defects during the formation of shallow p+/n junctions in the fabrication of ultralarge-scale integration devices. Ion implantation is a popular technique used to form shallow p+/n junctions with desired junction depth in Si. A study was therefore conducted that describes the removal of EOR defects in ion-implanted Ge+-pre amorphized Si by carbon implantation.

A study was conducted on the issue of nitrogen substitution in group IV elemental semiconductors especially the case of nitrogen in hydrogenated amorphous germanium (a-Ge:H). The experiment reports on the structural changes induced by the inclusion of nitrogen in the a-Ge:H network as monitored by infrared spectroscopy. The investigation used deposits of a-Ge(N):H samples having slightly larger nitrogen concentrations than those typically encountered in doping studies. Experimental findings are discussed.

Research was conducted to examine the variation of the structure and the electronic features of amorphous nitrogenated carbon films. Dual electron cyclotron resonance-radio-frequency plasma were used in the preparation of the carbon films while Auger electron spectroscopy, electron energy-loss spectroscopy, electron-spin-resonance spectroscopy and spectroscopic ellipsometry were used for the characterization of the film. Results demonstrate an inter-relationship between the electronic characteristics and structure of nitrogenated carbon films.

A study was conducted to enhance the bias-induced degradation in hydrogenated amorphous silicon thin film transistors by replacing the hydrogen in the film with deuterium. The Corning 7059 glass was utilized as a substrate. Chromium was evaporated on the glass substrate before a 50-nm-thick n+ a-Si:H was deposited on the chromium. Results indicated that the stability of amorphous silicon thin film transistors can be enhanced by using deuterium atom.

A study was conducted to investigate photoinduced optical phenomena in amorphous Sb2Se3-BaCl2-PbCl2 glasses using spectroscopic and theoretical quantum chemical techniques. Structural fragments in photoinducing changes were analyzed by Fourier transformation spectroscopy. Experimental results indicated that the glasses supported low nonuniformity and can be utilized as materials for picosecond infrared laser devices.

A study was conducted to determine circumferential magnetization curves for low, negative magnetostriction cobalt-rich amorphous wires supporting nominal composition under tensile stress using the magnetoimpedance effect. Frequency measurements were carried out in the 5 Hz-13 MHz range to determine spin rotation, domain wall bulging and wall displacement. Results indicated the damping of reversible magnetization processes by tensile stress.