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The stability of electron emission currents in diamondlike carbon (DLC) and hydrogen-free diamondlike carbon films deposited by plasma enhanced chemical vapor deposition were compared. The electron emission current for DLC was found to increase to 8100 s bias stress and then decrease with increasing bias stress time. For the hydrogen-free DLC, however, the emission current stabilized after the initial increase. The observed instability was attributed to the incorporated hydrogen.

Nucleation and growth of diamonds on SiO2-coated silicon substrate were systematically analyzed employing the microwave plasma enhanced chemical vapor deposition technique. Findings indicated that on both SiO2 and Si surface, diamonds started to nucleate at 240 sec. and fully covered the substrates at 300 sec. after the initiation of process. Nucleation of diamonds occurred through the exposition of Si dangling bonds and subsequently, the formation of sp3 bonds.

Charge trapping due to bulk trap generation during constant high field stressing is responsible for the breakdown of low pressure chemical vapor deposited oxides. The post-deposition annealing condition and deposition chemistry, influence the breakdown of charge in deposited oxides. With increased trapping in the bulk of the oxide, the Fowler-Nordheim tunneling current decreases in the oxides.

The heat transfer and particle deposition characteristics for the modified chemical vapor deposition method is analyzed. Axial variation in the tube wall temperature is quasi-steady. A two-torch formulation correctly predicts the wall temperature, which reaches a minimum after the torch. Increasing the flow rate of the carrier gas O2 increases the wall temperature and the rate of particle deposition, but decreases the efficiency. The effect of torch speed on the tube wall temperature, particle deposition rate, and the efficiency is also given.

Low oxidation state Ti compound, cyclopentadienyl cycloheptatrienyl titanium, is an appropriate Ti and TiN source for the chemical vapor deposition (CVD) of titanium nitride thin films under plasma enhanced conditions. The films have high nitrogen concentrations and do not reveal any grain columnar growth. CVD TiN functions as a diffusion barrier between silicon and aluminium at 575 degrees Celsius. The films comprise of 50% and 30% of bottom coverages and sidewall structures, with the structure and grain size of N2 and NH3 films being homologous. Lack of plasma excitation terminates the deposition.

A photo-CVD excimer lamp helps deposit silicon dioxide films at low temperatures and high deposition rates through the release of photon fluxes in the 172 nm wavelength band. Fourier transform infrared spectroscopy and ellipsometry help characterize the properties of photodeposited films. The photodeposition method lowers the hydrogen inclusion to low levels, making this technique suitable for electronic and thin film processing.

Auger electron spectroscopic and Fourier transform infrared spectroscopic studies reveal different compositions and structures for the silicon oxide interfacial layer growth at the Y2O3(film)-Si interface and thermally grown silicon oxide on bare Si. SiO2 layer grown at the interface of a thin Y2O3 film on Si exhibits more ordered coesite-like phase. Structure and optimization of SiO2 layer are vital for the application of Y2O3/SiO2 bilayer dielectric as a metal-insulator-semiconductor device.

Twin formation in diamonds is suppressed by controlling growth factor in vapor grown diamonds, thereby improving the defects in chemical-vapor-deposition (CVD) films. Transmission electron microscope reveals a complex of intersecting twin boundaries at the core of five-fold diamond crystals. The ubiquitous triangular defect does not exist in the substrate of the diamond and is eliminated by controlling growth conditions which produce defect-free diamonds. The diamond films are then free of the gently sloped equilateral triangular defect along the surface direction.

SIO2 molecules are deposited using SiH4 and N20 gases by the ultraviolet radiation produced by krypton pulsed lamp. The considerable absorption caused by OH groups is absent in the infrared spectra of these specimens. The ratio of the constituents has no influence on the refractive index of the films. The films have nitrogen, the composition of nitrogen is inversely proportional to the deposition pressure. The low intensity measurements of infrared absorption and refractive indese measurements confirm the deposition of SIO2 molecules.

The chemistry of the growth of diamond film by chemical-vapor deposition is investigated. A description of the reaction kinetics between diamond and a gas-phase species, such as H atoms, involved in its formation is given. The development of a simple method to measure the concentration of the H atoms enables the determination of the destruction probability of H atoms on diamond at 20 Torr and 1200 K. The destruction probability is found to be 0.12.

By applying both low-frequency wavelength modulation and high-frequency phase modulation to a laser diode, we develop a sensitive, high-bandwidth chemical diagnostic tool that is applicable to a variety of gas-phase processing environments. Specific chemical species are identified and monitored through their infrared absorption spectra, and the modulation methods allow for sensitive detection that is free of window and other reflection-driven interference fringes. Absorbance limits of 5.3 x 10 to the negative eighth power and 1.9 x 10 to the negative seventh power are obtained for an AlGaAs diode laser and a lead-salt diode laser, respectively. We discuss applications to plasma etching and chemical vapor deposition.

Deposition-induced damages in gallium indium arsenide (GaInAs) planar photodiodes were studied via chemical vapor deposition (CVD), plasma-enhanced CVD (PECVD) and ultraviolet activated CVD (UVCVD). Comparisons of the deep levels found in the photodiodes due to these three passivation methods were done. Sub-conduction band deep levels were observed in the photodiode structure at (0.19 + or - 0.03) and (0.35 + or - 0.03) eV. The first value, observed in PECVD and UVCVD passivated diodes, was ascribed to degradation of the GaInAs surface. The latter, measured in CVD passivated diodes, was related to the high temperature used during the CVD process.

A new cost-efficient sputter-slice technology for hard x-ray (10-30 keV) Fresnel zone plates fabrication, imposing no limitation to aspect ratio, is proposed. By means of a plasma chemical process, Si[O.sub.2][Si.sub.1-x][Ge.sub.x][O.sub.2] glassy film multilayer structures are deposited on a lateral surface of a silica rod, outermost layers being as thin as 100 nm. It has been shown by numerical simulation that for x = 0.2 germanium fraction, 100-300 [micro]m zone plate thickness and the number of zones of about 1000, first order diffraction efficiency as high as 20-30% at the energy of approximately 20 keV can be achieved. OCIS codes: 340.7450, 340.7440, 340.7460.

Atomic force nanolithography was used to fabricate the submicrometric catalyst patterns which were subsequently verified by selective growth of carbon nanotubes (CNTs). The results demonstrate that Atomic force microscopy (AFM) nanoindentation of a polymer film is an effective lithographic technique for the realization of very suitable catalyst nanopatterns for subsequent chemical vapor deposition (CVD) growth of multiwalled CNTs.

Infrared spectroscopy ellipsometry, cathodoluminescence and transmission electron microscopy are used to study the crystal structure and optical properties of thick AlN layers grown by hot-wall metalorganic chemical vapor deposition. The growth of thick AlN layers has benefited by performing the epitaxy on off-axis substrates since, due to stacking faults, the propagation of threading defects in AlN layers is stopped in a narrow interface region.

The electron mobility in the growth direction is measured by using space charge limited current techniques in device-type nin structure nanocrystalline Si:H and nanocrystalline Ge:H structures. The plasma-grown films have smaller grains and smaller mobilities and the mobility is found to increase with increasing grain size and with increasing temperature.

Zn3N2 polycrystalline films with n(super +)-type conductivity are grown by metalorganic chemical vapor deposition and rf-molecular beam epitaxy with carrier concentration in the range between 10(super19)and ~10(super 20) cm(super-3). Oxygen contamination without an intentional doing is found to be a cause of high electron concentration, leading to larger band-gap energy due to Burstein-Moss shift.

A formation technique is proposed for HfSiON film with an ultrathin SiO2 interfacial layer on the Si substrate by oxidizing the HfSiN film, which is deposited by using the metal-organic chemical vapour deposition reactor, and the leakage current of the metal insulator semiconductor (MIS) diode with HfSiON/SiO2 insulator of 1-nm equivalent oxide thickness is successfully decreased.

High-quality Schottky junctions are fabricated on n-type 4H SiC epitaxial layers grown by chemical-vapor deposition (CVD) on C- and Si-face substrates to understand the effect of growth direction on the growth mechanism and formation of defects. The Schottky junction fabricated on C-face SiC epilayers have displayed a lower leakage current, as compared with that of Si-face epilayers.

The effects of x on the crystal structure, and dielectric, ferroelectric, and piezoelectric properties of the (100)-/(001)-oriented epitaxial (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 films grown on the (100)(sub c)SrRuO3//(100)SrTiO3 substrates by metalorganic chemical vapor deposition are investigated. The mixed phase region of the rhombohedral and tetragonal phases is observed at around x values of 0.40-0.55 that is larger than those reported for sintered bodies and the single crystals.

Ni-Zn-Co ferrite films ([Ni.sub.0.16-0.21][Zn.sub.0.30-0.36][Co.sub.x] [Fe.sub.2.38-2.46][O.sub.4], x = 0~0.16) were deposited by spin-spray ferrite plating method at low temperature of 90[degrees]C. All the films had a saturation magnetization [M.sub.s] larger than 440 emu/cc. A small amount of Co substitution x into Ni-Zn ferrite films changed the magnetic anisotropy in film plane from isotropic to anisotropic and the magnetic easy axis was parallel to the flowing direction of the sprayed solutions on the rotating substrate. The coercivity [H.sub.c] and anisotropy field [H.sub.k] took small values of 10 and 25 Oe at x = 0.03. The complex permeability was measured in the range 20 MHz-3 GHz and very high static permeability [mu]' of 120 and resonance frequency [f.sub.r] of 900 MHz were achieved at x = 0.03. Exhibiting large [mu]'' > 30 even at 3 GHz, this Ni-Zn-Co ferrite film is applicable for wave absorbers to suppress the electro-magnetic interference among devices up to microwave frequencies. Index Terms--Ferrite plating, imaginary part of permeability, Ni-Zn-Co ferrite film.