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Several electrical in situ and ex situ measurements are conducted to study the influence of various environmental conditions, like dry oxygen and moisture on the electronic transport and device stability of the polycrystalline pentacene transistors. The analysis reveals that such conditions inhibits the injection of holes in the highest occupied molecular orbital level of the film, which further leads to an apparent reduction of the charge carrier mobility, as well as the threshold voltage.

The redistribution profiles of ion-implanted impurities during solid-phase epitaxy (SPE) are evaluated by using Rutherford backscattering spectrometry (RBS) and an analytical model is derived for these redistribution profiles. The model can be used to predict the impurity redistribution profiles after SPE, which can be used for the subsequent diffusion process.

The deep level defects in annealed InP are investigated by using photoluminescence (PL) spectroscopy, thermally stimulated current (TSC), deep level transient spectroscopy (DLTS) and positron annihilation lifetime (PAL). The results have identified the divacancy defect, its related PL emission and trap level.

The steady state Shockley-Read-Hall kinetics are used to study the effects of energy distributions of Si/Si[O.sub.2] interface traps in the energy gap oxidized silicon on the current versus voltage line shape of the electron-hole recombination current. It is concluded that the electron-hole traps at the Si/Si[O.sub.2] interface are more likely to have a U-shaped DOS than discrete few-level interface traps around the Si midgap.

The Si:H network was characterized during transformation from amorphous to micro- and nanocrystalline structures aided by increasing [H.sub.2] dilution to the Si[H.sub.4] ensemble in hot-wire chemical vapor deposition (HWCVD). The elevated [H.sub.2] dilution induced enormous polyhydrogenation and formation of lesser sense network full of voids, mostly around the tiny micro/nanocrystallites.

The effect of H doping in combination with various thermomechanical treatments given to materials, in order to identify conditions for maximum efficiency in the conversion of mechanical energy into heat at around room temperature was studied. It was observed that for appropriate alloy composition, the peaks occur at around room temperature (for acoustical frequencies), providing an opportunity to reduce machinery vibrations and noise pollutions.

The F control of the point defect density in preamorphized Si layers is studied by investigating the F incorporation process during the solid phase epitaxy (SPE) of amorphous Si layers. The results have demonstrated F to be a versatile and powerful tool to control the point defect density in Si, acting as a trap for the Is and indirectly modifying the diffusivity of dopants.

High-resolution x-ray scattering is used to study the effect of hydrogen implantation in silicon single crystals. The results have shown that a slight annealing required to form localized defects induces a strong reduction of the average strain level in the implanted crystal.

A novel self-aligned fully silicided (FUSI) gate process for the integration of platinum monosilicide (PtSi) as a metal gate for pMOS applications is described. The correlation between the work function shift caused by the segregated impurities at the gate/dielectric interface and the atomic size and surface dipole can be explained by the variation of the surface dipole, placing the impurity atoms exactly at the gate/dielectric interface.

Erbium-doped Si[O.sub.2] toroidal microcavity lasers are fabricated on a Si substrate using a combination of optical lithography, etching, Er ion implantation, and C[O.sub.2] laser reflow. Three-dimensional infrared confocal photoluminescence spectroscopy imaging is used to determine the spatial distribution of optically active Er ions in the two types of microtoroids, and distinct differences are found.

The microstructural evolution occurring within the eutectic SnPb solder during electromigration is investigated utilizing Blech specimens. Three-dimensional simulation is performed to examine the change in resistance and current-density distribution during electromigration.

CdGeAs2 crystals typically exhibit an absorption band near 5.5 mum that limits their use as a nonlinear frequency-conversion material in high-power infrared laser systems and this absorption band is related to the p-type nature of the as-grown bulk crystals. The variation in activation energy is correlated with p, and also with N(sub A) and finds excellent agreement with theory.

Effect of magnetic field on dislocation oxygen impurity interaction in silicon was investigated. The results revealed that dislocation-oxygen impurity interaction was influenced by treatments at very high temperatures and the critical stress for dislocation generation from a surface scratch varied with an intensity of the applied magnetic field and duration of magnetic treatment.

Numerous studies are used to investigate the polarization fatigue suppression behavior of the ferroelectric [Pb.sub.1-x][Ba.sub.x]([Zr.sub.0.52][Ti.sub.0.48])[O.sub.3] (PBZT) thin films, prepared by the sol-gel method. The results reveal that Ba doping of the substances leads to enhanced ion stability and suppressed oxygen vacancies, which ultimately results in an improved fatigue endurance of the substance.

Raman measurements are performed on ZnO bulk materials implanted with 220 keV [Mn.sup.+] ions with various doses. The results have shown that the Zn-related mode is the vibration of the Zn atom surrounded with the nearest Mn atoms, with the Mn atoms replacing the O atoms in the ZnO crystal.

The effects of doping on InAs/I[n.sub.0.15]G[a.sub.0.85]As quantum dots-in-well infrared photodetectors are studied by measuring the dark current, photocurrent, and spectral response. A significant reduction of dark current with decrease in doping concentration in the quantum dots is observed.