Photoinjection of electrons into silicon dioxide in metal-oxide-semiconductor (MOS) capacitors with 3.5 eV light is shown to create interface states with no apparent hole trapping precursor. The creation rate of these interface states depends strongly upon whether injection is from the gate metal or the silicon substrate, and on the forming gas annealing sequence used to passivate growth-induced interface states. A mechanism involving electron-induced release of hydrogen in the oxide is consistent with some aspects of the data.

Electron paramagnetic resonance (EPR), photo-thermal deflection spectroscopy (PDS), and electrical measurements have been used to characterize as-received and UV-lluminated lead lanthanum zirconate titanate (PLZT) and PZT ceramics. Following optical illumination we observe the activation of positively charged Pb+3 and negatively charged Ti+3 ions, as well as an increased broad absorption peak around 2.6 eV. The spatial distribution of the induced absorption correlates well with the location of the absorbed UV, suggesting that photo-produced carrier pairs are trapped at Ti+4 and Pb+2 producing the observed paramagnetism. The Ti+3 EPR spectra were successfully fit using the crystal field parameters derived from the PDS spectra. Preliminary results suggest that these charged paramagnetic ions can influence the electrical properties of PZT thin films. We investigated the effects of UV light and dc bias sequences by polarization-electric field (PE) measurements and find that the coercive fields are dependent on the sign of the applied bias during UV exposure. It is reasonable to expect that Pb+3 and/or Ti+3 ions act as the charge trapping sites which cause the threshold voltage shifts in the PE loop.

We have measured the optical absorption properties of Plasma Enhanced Chemically Vapor Deposited (PECVD) films of hydrogenated amorphous silicon nitride (a-SiNx:H) over the energy range from 0.54 to 2 eV using Photothermal Deflection Spectroscopy (PDS). The near-infrared absorption properties of these films provide a quantitative estimate of the amount of H bonded to Si or N as well as a measure of the the density of electronic gap states due to species like Si dangling bonds. Typical PDS spectra obtained on as-deposited films show a broad absorption tail with a large number of narrow absorption peaks. Using the phase sensitive feature of this spectroscopy we are able to separate nitride-related absorption from that arising from the fused quartz substrates. In addition to the broad, featureless band tail, whose magnitude is quite sensitive to optical excitation with light above ̃3.9 eV, we observe a number of narrow absorption peaks which we identify as overtones of localized vibrational modes. Specifically, we see peaks at 0.82 and 1.20 eV which we identify as the 1st and second harmonics of N-H stretching vibrations, and several other peaks whose origins remain undetermined. Prolonged UV excitation produces no detectable change in these vibrational modes, although large changes are seen in the underlying absorption tail. This reinforces previous suggestions that photoinduced changes in these films do not arise from rearrangement of the bonded hydrogen.

Prototype ferroelectric thin film, nonvolatile memory, nondestructive readout (NDRO), semiconductor devices have been fabricated. The “1” and “0” logic states of these prototype devices are in principle determined by the modulation of the conductivity of a semiconductor film channel by the polarization state of the underlying ferroelectric thin film layer. Programmed resistance ratios of the two logic states of 5:1 are demonstrated. While the best performance to date has been achieved for devices that have a 40 nm ln2O3 film covering a 300 nm thick PZT 20/80 layer, we also develop criteria for selecting semiconductor films that will improve performance for this NDRO device design. Among the other semiconductor films that are characterized with respect to this criteria are boron doped Ge, ZnO and aluminum doped ZnO. It is demonstrated that by appropriate donor doping of ZnO films the effects of intrinsic defects are masked and that process temperatures can be extended by 300×C.

Examination of capacitance transients arising from the emission or capture of electrons at a charged GaAs grain boundary reveal for the first time the existence of discrete interface levels. The position of these levels in the bandgap and their associated capture cross sections are determined from the transients.

Rutherford backscattering, Van der Pauw and TEM measurements were used to characterise the annealing behaviour of antimony implanted LPCVD polysilicon. High electrical activity without dopant redistribution was obtained for 600°C annealing of 1 × 1015 cm−2 and 3×1015 cm−2 antimony implanted samples. Subsequent annealing at temperatures ≥900° C resulted in considerable grain-boundary-assisted redistribution of antimony within the polycrystalline layers and associated changes in sheet resistance. Our results suggest that the sheet resistance of the films is controlled by dopant segregation at grain boundaries and the fraction of antimony distributed on active sites within individual grains.

A reversible change in barrier voltage is observed in assintered ZnO varistors upon application and removal of the applied voltage. This is attributed to a metastable component in the grain boundary Schottky barriers. Varistors show improved stability when the metastable component is removed or fixed by heat treatment.

Modern physicalists frequently offer the generous concession that although dualism is false, it is not a metaphysical impossibility. And it appears that the proper formulation of physicalism allows for this concessionary position. It would be expected that dualists also could accept that while physicalism is false, it too is a metaphysical possibility. I will argue that a careful analysis of physicalism and dualism shows that in fact these concessionary positions cannot be maintained. In particular, the nature of the metaphysical determination relation which holds between matter and mind on both physicalist and dualist views precludes either from allowing that the other is a metaphysical possibility.

We compute theoretical infrared light curves for several known extrasolar planets. We have constructed a set of routines to calculate the orbital parameters for a given planet and integrate over the planetary disk to determine the total flux density of the planet as it orbits the parent star. We have further developed a spectral synthesis routine to calculate theoretical spectra of extrasolar giant planets from 3–24 $\mu$m. The code requires a temperature-pressure profile as input, calculated by solving the radiative transfer equation; it then calculates continuous opacities and line opacities for water, carbon monoxide, and methane, and finally integrates over the layers of the atmosphere to determine the emergent flux. By integrating the theoretical spectrum over the bandpass of a particular instrument and including realistic instrument noise, we produce a set of multi-wavelength, infrared light curves. Using these light curves, we predict whether a particular known planet can be observed and characterized using the Spitzer Space Telescope, as well as other proposed space-based instruments, such as the Fourier-Kelvin Stellar Interferometer (FKSI) and the James Webb Space Telescope (JWST).

Perhaps the Clearest and most impressive use of the Principle of Continuity by Leibniz in the evaluation of a theory is that offered in refutation of the Cartesian laws of motion, as given in his Critical Remarks Concerning the General Part of Descartes' Principles. With regard to the Cartesian laws of impact Leibniz says:

On Article 49. Rule 4. If B, which is moving, is smaller than C, which is at rest, B will be reflected with the velocity it had before the shock while C will remain at rest.