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Research on silicon oxide films is examined in detail, including the significance of spectra frequency shifts and how the model can explain them.

Research describing the dielectric properties of silicon oxide films is presented. In particular the dielectric contribution of ionic, electronic and and dipolar polarization is investigated.

Research describing the relationship between degradation and breakdown of ultrathin silicon dioxide is presented. In particular the effects of substrate hot hole injection are investigated.

Gate inversion current in metal-oxide semiconductor (MOS) tunneling diodes with different substrate doping is examined.

Synthesis of a high-quality graded oxide is described. Grading is accomplished by growing a high-temperature oxide above the silicon dioxide viscoeleastic temperature under a pregrown lower-temperature silicon dioxide layer.

The effect of hydrogen absorption on the bulk of amorphous SiO2 thin films is investigated.

Electrical properties of silicon oxide films grown by oxygen radical generated in Kr/O[sub 2] mixed high-density, microwave-excited plasma at 400 degrees centigrade are investigated. Such films have excellent electrical properties, even in ultra-regions.

Research is presented concerning the use of Fourier transform infrared spectroscopy to investigate the characteristics of ultrathin silicon oxide films. The films were thermally grown on Si (100).

Research describing germanium nanocrystal growth is presented. In particular the characteristics of growth in silicon oxide film is investigated by x-ray photoelectron spectroscopy and transmission electron microscopy.

Thick silicon dioxide films were studied to model the stress-induced leakage currents, using two stage inelastic trap assisted tunneling.

A new study investigates the hydrogen dynamics of the dielectric degradation of SiO2 induced by electronic excitation.

A new study investigates the mechanical stress in thermally grown SiO2 films on Si during 4 Me V Xe ion irradiation.

A new study investigates the optical and microstructure properties of porous silicon film grown at low current densities.

A new study aims to prepare glass thin films with enhanced second-order optical nonlinearity by applying UV poling to Ge-doped SiO2 thin films.

A new study investigates the degradation of the dielectric breakdown field of thermal SiO2 film caused by voids in Si wafers.

Si nanocrystals formed by high temperature annealing of Si oxide thin film were studied.

Leakage currents and dielectric breakdown have been studied in MIS capacitors of metal-aluminum oxide-silicon. Thermal oxidation, which was studied, gave Al(sub.2)O(sub.3) with thickness and structure dependent on process time and temperature. Best electrical properties were seen when AlN was oxidized fully leaving no residue. For reliability of circuits working under extreme conditions it may be important that temperature dependence of the current vs electric field showed the conduction mechanism to be Frenkel-Poole emission and that higher temperatures were seen to reduce current.

Results show that leakage tunneling through thin gate oxides is reduced by the nitrogen-rich layer present at the SiO(sub)2/Si substrate interface.

Results show a a linear relationship between silicon-silicon bond strength whereas no correlation between silicon-hydrogen bond strength. Data suggest that highly stable and mobile thin film transistors required a dense amorphous silicon:hydrogen layer with compressive stress characteristics.

Results demonstrate that scanning tunneling microscopy and the generated spectra are useful in studying the local process-related damage of silicon oxide ultrathin films during fabication of devices. Data further show that ion-beam damage of the film is recovered during thermal annealing.

Results show that the ab initio molecular orbital calculations simulating the layer controlled silicon dioxide growth on Si(001) agree with experimentally derived data only in the absence of the catalyst.

Research is presented into the effect of density of Ge nanocrystals on violet-blue photoluminescence of Ge+-implanted SiO2 film.

A new study presents time-resolved photoluminescence decay measurements for Si nanocrystals embedded in silicon dioxide.

A new study investigates the density of ultrathin silicon oxide films grown on p-type Si(100) at various humidities during dry oxidation.

The effects of thermal annealing on the optical and structural properties of Ge-doped SiO2 thin films have been studied. The films have been prepared through chemical vapor deposition (CVD) and flame hydrolysis deposition. Results indicate that thin films formed through CVD have inhomogeneous Ge distribution with Ge oxygen-deficient centers. However, the Ge distribution became uniform when the films were annealed at temperatures higher than 800 C. There was also a reduction in the number of oxygen-deficient centers when annealing was done in an O2 atmosphere.

The three omega thermal conductivity measurement method has been applied to determine the thermal conductivities of SiO2 films on Si substrates and of a chemical vapor deposition (CVD) diamond plate. Results indicate that SiO2 films have a thickness-dependent thermal conductivity. On the other hand, the CVD diamond plate was observed to demonstrate thermal conductivity gradient through the thickness and interfacial thermal resistance.

Research was conducted to examine the charge trapping and the depth profiles of the irradiation damage introduced by electron bombardment during Auger electron spectroscopy (AES) on SiO2. An environmental AES and specimen heating were used for the charge reduction. Results indicate that the E' centers, peroxy radicals and nonbridging oxygen hole centers are responsible for the efficient trapping of electrons.

Research was conducted to examine the microstructure, atomic density and electrical resistivity of reactively sputtered Ru-Si-O ternary films.The evolution of some of the properties upon heat treatment was analyzed within the framework of a ternary phase diagram from the Ru-Si-O system. Results suggest that changing the Ru:Si ratio will lead to major differences in the resistivity of oxygen-saturated layers after thermal annealing.

Research was conducted to examine a new approach for describing the conduction mechanism in stress-induced leakage currents (SILC) in ultrathin silicon dioxide films. The new evaluation results in analytical expressions capable of reproducing the SILC in an 6.8-nm-thick ultrathin silicon dioxide film. Results provide an explanation for the conduction mechanism leading to SILC which is useful in the development of thin gate oxides used in ultralarge scale integration device technology.

Research was conducted to examine a novel formation phenomenon in reflected light that occurs during the photochemical fabrication of Gaussian shaped porous Si thin films. The effect was observed to be caused by Fresnel diffraction and optical interference. Results demonstrate that not only does the patter size depend on the depth of the reflecting interface but also that if a por-Si film is present above the reflecting interface, the index of refraction of por-Si plays a role in determining the pattern size.

The influence of oxidation on bulk trap and interface states near the SiO2/SiGe interface has been investigated. The results of capacitance deep level transient spectroscopy showed that two peaks at the energy level 0.23 eV (D1) and 0.40 eV (D2) below the conduction band edge are present. The results also showed a characteristic feature of interface states for the D1 peak, while the annealing behavior of the D2 peak indicates that D2 is a divacancy related bulk trap.

The germanium nanocrystals embedded in amorphous silicon oxide films which were synthesized by rapid thermal annealing have been characterized. The samples were prepared by cosputtering germanium and silicon oxide targets by a radio frequency magnetron sputtering machine, and were analyzed by Raman spectroscopy. The results showed a transition spectra from amorphous to nanocrystalline germanium for samples which were annealed between 600 and 750 degrees C. The estimated crystal size was between 29 and 66 angstrom.

Research was conducted to examine the characteristics of SiO2 film and the Si/SiO2 interface formed by remote plasma enhanced chemical vapor deposition with the addition of chlorine into SiH4-N2O. Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, ellipsometry, secondary ion mass spectroscopy, electron spin resonance, transmission electron microscopy and atomic force microscopy were used to characterize the SiO2 films deposited with the chlorine addition.

The optimum Magnetron-plasma-enhanced chemical vapor deposition conditions required to obtain superior SiOx barrier coatings deposited on poly(ethylene terephthalate) (PET) were determined using a Non-Parametric Response Methods algorithm. Results reveal an Arrhenius behavior displayed by oxygen and vapor permeances of optimized PET/SiOx composites. The thermal activation energy for water vapor permeation was found to depend on barrier performance and increases with an increase in barrier efficacy.

Depth-resolved measurements of the photoluminescence of Si implanted and annealed SiO2 films on Si were conducted to obtain the depth distribution of luminescent Si nanocrystals. It was observed that the defect luminescence centered around lambda = 600 nm mostly comes from a approximately 15 m-thick near-surface region. Large Si nanocrystals emitting at lambda = 900 nm were mostly found in the center of the oxide film, where the Si concentration was highest.

Research was conducted to examine the structural changes in plasma-deposited fluorinated silicon dioxide films caused by fluorine incorporation using ring-statistics based mechanism. Fourier transform infrared spectroscopy studies and molecular orbital modeling were employed to explain structural changes in plasma-deposited SiOF films caused by fluorine incorporation. Results demonstrate that an increase in the average Si-O-Si angle within SiOF network with increasing fluorine doping level can be explained based on the corresponding changes in ring statistics of the SiOF network.

Research was conducted to examine the temperature dependence of the properties of heteroepitaxial Y2O3 films grown on Si by ion assisted evaporation. Reflection of high energy electron diffraction, X-ray scattering, Rutherford backscattering spectroscopy channeling, atomic force microscopy and transmission electron microscopy were used to investigate the film properties such as crystallinity, strain and morphology. Results indicate that many defects at the interface region were generated by interface interaction between the Si substrate and the yttrium metal.

The production of interface states by electron injection in n- and p-type (3C,4H,6H)-SiC/SiO2/metal structures was investigated by photoinjection techniques. The charge trapping in the oxides in SiC was observed to be similar to the charging of thermal oxides on Si. However, the production of interface states in SiC/SiO2 was larger than in Si/SiO2. The interface-state generation was observed to be enhanced on the C face of SiC as compared to the Si face, was also seen to be enhanced after carbonization of the SiC surface before oxidation.

A study was conducted to analyze the dependencies of MeV He single-ion-induced interface traps on oxide thickness and oxide electric fields during irradiation. Results indicated that the generation rate of interface traps per ion for thicker oxide metal-oxide-semiconductor field-effect transistors was greater than that for thinner oxide metal oxide semiconductor field effect transistors during a positive electric field.

A study on the use of granular magnetic thin films as ultra-high density recording media was conducted to investigate magnetic interactions in very thin Fe-SiO2 films. The experiment constructed delta m plots for granular thin films. Measurements of the activation volume for the thinnest films suggest 2D interactions rather than 3D interactions which are associated with very low values of the magnetic viscosity. Experimental methods and results are presented.

This work presents a new strain sensor with a compact structure. The strain sensor comprises of a pair of cantilever beams with different lengths connected by a short tip. The residual strain causes two beams to deflect each other, thereby magnifying the deflection, which is measured by the tip. The displacement is independent of both Young's modulus and the film's thickness. An analytical model is derived to relate the measured displacement to residual strain. Finite-element modeling is also used to analyze the model. This work also thoroughly considers other factors that influence the designs and the implicit limitations of the strain sensors. Experimental results with an Si[O.sub.2] film as well as undoped LPCVD polysilicon films are used to demonstrate the effectiveness of the proposed structure. Index Terms - Residual strain, thin film.

A new Nb/Al-AlO(sub x)/Nb integrated circuit process with very small critical current spread was developed. It was designed to precisely control critical parameters for large scale integration. Several improvements such as the use of Electron Cyclotron Resonance Plasma Enhanced Chemical Vapor Deposition were made to reduce critical current and other parameter spreads. The new process is reviewed as well as its fabrication.

Metal alkoxides as the starting precursor materials were used as the metal deposition technique to grow metal oxide films on single crystal oxide substrates and deformation textured metal substrates. The grain alignment, morphology and crystallinity of the oxide films depended on the process conditions and the substrate properties. A range of oxygen partial pressures and temperatures were used in growing epitaxial oxide films on technologically important metal substrates.

Research was conducted to characterized the crystallinity of laser-recrystallized Si films on insulators using micro-Raman imaging. To probe the structure at various depths, a small-angle bevel made by angle lapping of the SOI film was used. The depth profile of the Raman feature reveals that the defect density is high in the region near the interface of Si and SiO2 and that the stress increases toward the top surface of the silicon film.

Research was conducted to examine the phenomena of energy transfer from Si nanocrystals (nc-Si) to Er ions inside the SiO2 surrounding the nc-Si or at the nc-Si/SiO2 interface, and the origin of the characteristic double photoluminescence (PL) peaks in the SiO2 film containing nc-Si and Er ions. Results based on the quantum confinement-luminescence center model reveal that the PL peak at 1.53 eV most probably originates mainly from another type of defects or impurities in the SiO2 barrier or at the nc-Si/SiO2 interface.

Research was conducted to examine the local dielectric breakdown of ultrathin SiO2 films grown on silicon substrates using scanning tunneling spectroscopy and scanning tunneling microscopy. A leakage current was observed at the quasibreakdown spots that passed through defect levels in the ultrathin oxide films. Several tunneling spectra derived from near leakage sites were also found to have clear negative differential resistance.

Research was conducted to examine a metal-oxide-silicon capacitor under constant voltage using tunneling Fowler-Norheim bidirectional electron injections. Defects generated within the oxide were found to be of the same physical nature and are mainly composed of neutral traps. Results demonstrate that the saturation of interface state generation is linked to the polar bonds at the silicon/oxide interface.

A study was conducted on the characteristics of electron capture after hot-hole injection into a 131-A silicon dioxide, which was then compared with those after Fowler-Nordheim electron injection. Positive charges were accumulated in the oxide after hole injection from the silicon substrate into the oxide. The low-field electron capture observed may be explained based on the electron tunnelling from the substrate into the positive charge and neutral trap centers created near the substrate-SiO2 interface.

A study was conducted to analyze the interaction of copper, palladium and cesium atoms on regular and defect sites on the SiO2 surface using cluster models. Hartree-Fock, density functional theory and multireference configuration interaction techniques were utilized to determine the bonding of the metal atoms at several sites. Results indicated that the two-coordinated bridging oxygens of the triple bond surface of Si-O-Si are unreactive.

Si surface irradiation with O2+Ar electron cyclotron resonance microwave plasma was employed to grow ultrathin silicon oxide films at low temperatures. Using Fourier transform infrared reflective absorption spectroscopy that employed polarized light, the equation of the dependence of growth rate and film quality on the working pressure were analyzed. Further, very thin layers were detected and described by using the longitudinal-optical phonon mode. The results are discussed.