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A prism coupler is used for examining the polarization-dependent optical properties of slab waveguide films, which are composed on nanoparticles dispersed in a Si[O.sub.2] matrix. The optical spectra of the nanocomposite films are compared with those of cosputtered films and the optical anisotropy of the films are modeled and analyzed based on an effective medium theory with Maxwell-Garnett geometry and layer-by-layer photonic band-gap structures.

The effect of copper precipitation on the formation of denuded zone (DZ) in Czochralski silicon is examined by using scanning infrared microscopy (SIRM) and optical microscopy. The formation of DZ is affected by the copper precipitation mechanism, which is controlled by the annealing temperature and point defects.

The small signal gain measurements of optically excited terahertz Si:P and Si:Bi lasers are presented. It is found that the silicon lasers are optically excited with radiation from a free electron laser or a C[O.sub.2] laser.

Growth of [Si.sub.1?x][Ge.sub.x] nanodots on Si substrates is accomplished using single source gaseous precursors. It is found that on the nanodots they are relaxed and their compositions correlate with the molecular ratios in the precursors used in their fabrication.

Large-scale aligned silicon carbonitride (SiCN) nanotube arrays are synthesized by microwave-plasma-assisted chemical vapor deposition by using Si[H.sub.4], C[H.sub.4], and [N.sub.2] as precursors. With the increasing Si concentration, the SiCN nanotube has displayed favorable oxidation resistance, suggesting that SiCN nanotube is a promising candidate as stable field emitter.

The x-ray absorption fine structure (XAFS) spectroscopy was used to study the microstructure and electronic structure of epitaxially grown GaN which was subjected to high-dose Si implantation. The analysis of the extended XAFS spectra reveals that implantation with 100 keV Si ions with a fluence equal to 1 * [10.sup.18][cm.sup.-2] renders the material amorphous and promotes the formation of Si-N bonds with a bond length equal to that corresponding in S[i.sub.3][N.sub.4].

A silicon carbide layer is synthesized by the implantation of a p-type (100) Si waver at an elevated temperature and the crystallinity is enhanced by subsequent MeV low fluence heavy ion irradiation. The results have shown an enhancement of the crystallinity using higher energies, higher substrate temperatures of the high-energy heavy ion bombardment, indicating that electronic stopping plays a vital role in modifying the SiC crystal.

The temperature dependent Hall effect (TDH), thermal and optical admittance spectroscopies and secondary ion mass spectroscopy (SIMS) are used to study the deep levels in high purity semi-insulating 4H-SiC. The results have shown that the compensation in the material is a complex process that has involved multiple deep levels.

A study was conducted to investigate AlGaN potential barrier heights of AlGaN/GaN heterostructures with and without SiN passivation. Catalytic chemical vapor deposition (Cat-CVD) SiN passivation lowered the AlGaN potential barrier height more significantly than plasma-enhanced CVD (PECVD) SiN passivation, suggesting that the passivation method could influence the AlGaN potential barrier height.

Boron [delta] doping in the Si spacer is used to show the broadband absorption of metal-oxide-semiconductor SiGe/Si quantum dot infrared photodetectors. Broadband detection is feasible using this device because the atmospheric transmission windows are located at 3-5.3 and 7.5-14 [micro]m and it should be noted that the detector should be operated in the inversion bias region to reduce dark current.

Fabry-Perot (FP) effects found in InGaN/GaN heterostructures and quantum wells epitaxially grown on Si(111) substrates have resulted from the high refractive index contrasts at the GaN/Si and the Air/InGaN interfaces. A three-layer FP model is used to describe the cavity and optically pumped lasing in nitride vertical-cavity surface-emitting laser is shown at room temperature.

The luminescent properties of concentration dependence are found in Ba[Mg.sub.2][Si.sub.2][O.sub.7]:[Eu.sup.2+], [Mn.sup.2+] red phosphor. The analysis of the energy transfer from [Eu.sup.2+] to the two [Mn.sup.2+] centers has indicated that the number ratio of [Mn.sup.2+](II) to [Mn.sup.2+](I) has increased with increasing [Mn.sup.2+] concentration.

A molecular dynamics (MD) model is used to examine both the deposition and etching steps during the layer-by-layer etching of Si and Si[O.sub.2]. The results have shown that fluorocarbon passivation films can be grown in a self-limiting manner on both Si and Si[O.sub.2] by using low-energy C[F.sub.2.sup.+] and C[F.sub.3.sup.+] ions.

Large-scale amorphous silicon oxide nanowires (SiONWs) are synthesized from silicon monoxide powder under supercritically hydrothermal conditions. The [triple bond] Si-OH can reduce the adsorption activity of the SiONW surface that might be in favor of preventing the growth from the cross section and assisting the growth along the axial direction of the SiONWs.

The enhancement of ultrathin silicon oxide/Si(100) films and the effect of fluorine on it is investigated by performing in situ pyrolytic-gas passivation (PGP) using N[F.sub.3] simultaneously with the previously proposed PGP using [N.sub.2]O. The results have shown that F passivation effectively contributes to compensate the inconsistent-state bonding sites near the interface that remain with N passivation.

An extended Mie-Gruneisen molecular model is presented, which describes a bond-breakage process for O-Si equivalent to [O.sub.3] tetragonal molecules in silica and the trap-generation process that occurs during time dependent dielectric breakdown (TDDB) testing. The molecular model shows clearly that current included hole capture and hydrogen release could play critically important roles in the TDDB process.

Homoepitaxial silicon thick films are produced by medium pressure plasma chemical vapor deposition at rates as fast as 60nm/s and at a temperature of around 700 degree celsius, with a aline gas partial pressure of 4mTorr. The rate for epitaxial growth is observed to increase linearly with saline gas partial pressure.

The growth dynamics and the morphology of Ge quantum dots (QDs) grown on Si (100)-(2 X 1) by pulse laser deposition (PLD) are studied by reflection-high energy electron diffraction (RHEED) and atomic force microscopy (ATM). The effect of the laser fluence on the growth dynamics and cluster morphology is also studied.

Hugoniot equation-of-state data of shock compressed beta-Si4Al2O2N6 are determined to a pressure of 120 GPa. A comparison of the Hugoniot data and recovered samples suggests that the high-pressure CaTi2O4-type phase is not quenchable and quenched as an amorphorus phase although a large hysteresis is detected in the release path.

A study was conducted to investigate the mechanism of Hf silicidation from HfO(sub 2) gate insulators on Si by high-resolution core-level photoemmision spectroscopy temperature with detailed anneling-temperature controlling. The results showed that the silicidation temperature depends on the difference of the chemical states at the interfacial layer.

Carbon nanotubes (CNTs) were grown on Si substrates by rf CH4 plasma-enhanced chemical vapor deposition in a pressure range of 1-10 Torr, and then characterized by scanning electron microscopy. At 1 Torr, the CNTs continued growing up to 60 min, while their height at 4 Torr had leveled off at 20 min.

Electroluminescent ZnS:Mn thin films were deposited by the atomic layer deposition (ALD) technique. The results show that a relatively small change in the Zn precursor can have a clear impact on the electro-optical properties of the devices, and that a mixed halide/metalorganic ALD process can produce an electroluminescent device that ages relatively slowly.

The growth and characterization of a depth-graded multilayer suitable for use as a zone plate for hard x-ray focusing is reported. The multilayer has a total of 470 alternating layers of WSi2 and Si with thicknesses increasing monotonically from 15 to 60nm, for a total thickness of 11.33 (mu)m.

The aging processes of magnetron-sputtered Si-SiO(sub x) structures with silicon quantum dots are investigated by photoluminescence, electron paramagnetic resonance, infrared absorption, and Raman-scattering methods. It is shown that Si-SiO(sub x) layers in contrast to porous silicon, the intensity and spectral position of the emission band caused by exciton recombination in Si crystalline do not change practically during aging.

The behavior of light-induced degradation in nc-Si:H solar cells under various electrical bias conditions is studied. There is no forward-current-induced degradation in the dark and an enhanced light-induced degradation under reverse bias.

A model for the oxidation of SiGe that takes into account the participation of both the Si and the Ge in the oxidation reaction as well as the replacement of Ge in mixed oxide by Si is demonstrated. An effective diffusivity approximation to the Si-Ge interdiffusion on the underlying layer, together with approximate boundary conditions, give reasonable agreement with published results on the formation of a Ge-rich layer.

SiO(sub x) nanowire bunches are fabricated on Ni(NO3)(sub 2)6H2O solution-coated Si(111) substrates in a chemical vapor deposition system in the presence of Ga and under the flow of Ar and NH3 gases. Results reveal that Ni and Ga act as catalysts for the growth, while nickel nitrate hydrate serves as a source of oxygen.

Coplanar high-resolution x-ray diffraction is used for the characterization of size, chemical composition, and strain of Ge/Si (001) islands in a three-dimensional island crystal grown using self-assembly on a prepatterned (001) Si substrate. The Ge content in the islands is found to be on the average 40%, while the island shape does not change dramatically during capping.

The effect of the configuration of oxygen on the electronic structure of H-covered Si nanocrystals and the mechanism of the observed redshifts in photoluminescence (PL) is evaluated by simulating a Si nanocrystal by a spherical quantum dot and performing electronic state calculation. The comparisons of the results reveal that the backbonded oxygen configuration would be more probable than the double-bonded oxygen configuration.

A study is carried out in which synchrotron-based x-ray absorption microspectroscopy (mu-XAS) is applied to identify the chemical states of copper-rich clusters within a variety of silicon materials. The results show the effectiveness of aluminum gettering for the removal of copper from bulk silicon that is quantified via x-ray fluorescence microscopy and a segregation coefficient is determined from experimental data to be at least (1-2)*1000.

The amorphous siliconlike thin films deposited by plasma-enhanced chemical-vapor deposition using hexamethyldisiloxane as monomer and Ar as feed gas is investigated for their optical and structural properties as a function of the deposition power, in the range of 100-400 W. The automic force Microscopy analysis confirms the amorphous character of the films and shows how the deposited layers become flatter and more compact when power increases.

A numerical model of plasma-enhanced chemical-vapor deposition of hydrogenated microcrystalline silicon film from SiH(sub 4) and H(sub 2) gas mixtures in a capacitively coupled radio-frequency plasma reactor is presented. The numerical results of the deposition rate as a function of the plasma reactor operating parameters show good agreement with experiments.

It has been shown in this article that for the growth of thin oxides two mechanisms have to be taken into account. They are the reaction of silicon and oxygen at the Si/SiO2 interface as well as at the SiO2/gas interface.

A detailed quantum chemical study of atomic layer deposition (ALD) was made. The growth mechanism of SiO2 on bare Si (100)-2*1 surface using SiC4 and H2O as precursors was made.

Effect of preanneal ion irradiation on the formation of luminescent Si nanocrystals in electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD) deposited silicon-rich silicon oxide (SRSO) films was investigated. Low-dose ion irradiation would be an effective way to homogenize PECVD-deposited silicon-rich silicon oxide films.

The chemical bonding and elastic properties of Li2SiZn is investigated using ab initio calculations. It is concluded that chemical bonds are of ionic nature and the bulk moduli calculated are 42 and 22 GPa.

The photomodulated optical reflectance (PMOR) technique is employed to explain the signal behavior exhibited by the active doping profiles in silicon. The Auger recombinations and the ambipolar diffusion are shown to be some of the main forces acting on the free carriers of the system.

The article presents a complete study of the various electrical properties exhibited by the metal-insulator-silicon capacitors with pyrolytic carbon electrodes. The results demonstrate the absence of a depletion region between the dielectric and the carbon in the system.

A combination of the x-ray photoelectron spectroscopy and x-ray photoelectron spectroscopy techniques is employed to explain the chemical interactions taking place between the [B.sub.4]C, B, and C and the Mo/Si layered structures. The stability of the compound thus formed is shown to be the main determinant of the diffusion barrier function of the [B.sub.4]C interlayers.

(1-x)Pb([Zr.sub.0.4],[Ti.sub.0.6])[O.sub.3]-(x)Bi([Zn.sub.0.5],[Ti.sub.0.6])[O.sub.3] (PZT-BZT) films are deposited onPt(111)/Ti/Si[O.sub.2]/Si(100) substrates by chemical solution deposition by using spin-coating. The ferroelectric properties of PZT-BZT films are examined and the impact of BZT doping on the structure of PZT is examined by x-ray photoelectron spectroscopy.

The impacts of carrier recombination at the surface as well as in the substrate are examined by using numerical simulation based on a diffusion equation. The simulation has shown that a very thick epilayer is needed for accurate measurement of carrier lifetimes of n-type 4H-SiC epilayers if the bulk lifetime in the epilayer is longer than several microseconds, due to the extremely short lifetimes in the substrate.

Several studies are conducted to explain the presence of the enhanced collection efficiency in the thin film silicon solar cells. The collection efficiency is shown to be completely dependent on the intensity of the bias and the monochromatic light.

Several studies are conducted to explain the several different resonant characteristics of the different doubly-clamped ultranarrow SiCN nanochemical resonators. A decrease in the width of the resonator is shown to lead to a large decrease in the resonant frequency.

Several electrochemical capacitance-voltage measurements are conducted to determine the electron and hole mobility reduction taking place in the majority carrier holes of the compensated p-type silicon. The Hall factor for the compensated, as well as the noncompensated compounds is also determined.

Several studies are conducted to explain the impact of the single donor on the transport properties and negative differential resistance existing in silicon n-type nanowire metal-oxide-semiconductor transistors.

Several studies are conducted to explain the synthesis, as well as the different physical properties of the porous silicon carbide (SiC) ceramics. The phase composition and properties of the ceramics are shown to be highly dependent on the initial Si contents and the temperature.

Quantum cascade lasers (QCLs) are compact sources that have shown high output powers at terahertz (THz) frequencies. The results are described from [Si.sub.1-x][Ge.sub.x] quantum cascade superlattice designs emitting at around 3 THz that are grown in two different chemical vapor deposition systems.

Modification introduced in the electrochemical etching procedure together with postetching treatment in [H.sub.2][O.sub.2] has led to a decease in the nanocrystalline core size and also the changes in the surface oxide. The discontinuity of the spectral shift and possible relation between both bands are described.

A noncharge-sheet channel potential and drain current model is described for long-channel dynamic-depletion (DD) silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistors (MOSFETs). The three-interface analysis based on the universal channel potential solution is used for deriving a unified noncharge-sheet drain current expression.

The energy band gap, alignment with Si and the chemical bonding of [Hf.sub.x][Si.sub.1-x][O.sub.2] films are examined as a function of composition. The changes in the band structure and band alignment of Hf-silicate films are described based on the chemical structure of the nitrided Hf-silicate films.