The elastic coefficients for an arbitrary rectangular coordinate system are calculated as a function of direction cosines in the crystal. Young's modulus, shear modulus, and Poisson's ratio are defined in general and values tabulated for some of the more important directions in the crystal. Graphs of these moduli are also plotted as a function of crystal direction for orientations in the (100) and (110) planes as well as planes determined by the [110] direction and any perpendicular direction.

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The effect of dielectric constant and barrier height on the WKB modeled tunnel currents of MOS capacitors with effective oxide thickness of 2.0 nm is described. We first present the WKB numerical model used to determine the tunneling currents. The results of this model indicate that alternative dielectrics with higher dielectric constants show lower tunneling currents than SiO 2 at expected operating voltages. The results of SiO 2 /alternative dielectric stacks indicate currents which are asymmetric with electric field direction. The tunneling current of these stacks at low biases decreases with decreasing SiO 2 thickness. Furthermore, as the dielectric constant of an insulator increased, the effect of a thin layer of SiO 2 on the current characteristics of the dielectric stack increases. Semiconductor Research Corporation (SRC Contract 132).

High-frequency capacitance-voltage (C C C-V V V ) measurements have been made on ultrathin oxide metal-oxide-semiconductor (MOS) capacitors. The sensitivity of extracted oxide thickness to series resistance and gate leakage is demonstrated. Guidelines are outlined for reliable and accurate estimation of oxide thickness from C C C-V V V measurements for oxides down to 1.4 nm.

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Increasing concerns regarding litigation and terrorism provide a strong dual motivation to decrease high explosives usage in the construction industry. This paper provides parameter considerations and initial guidelines for the application of expansive fracture agents, typically used for concrete and soft rock removal. This approach may be especially appropriate near environmentally and historically sensitive sites. Thirty-three unreinforced blocks (approximately a cubic metre each) of varying strengths, composed of sand, cement, and fly ash, were tested under various temperature environments, with differing expansive agents, confinement levels and post-cracking treatments. Cracking characteristics such as crack initiation and crack expansion were analysed. Although the performance of expansive cement was dependent on a highly complex set of variable interactions, higher ambient temperatures, higher agent mixture temperatures and chemical configuration designed for colder temperatures decreased the time to first crack and hastened the extent of cracking. Conversely, higher strength material required more time to first crack, as well as an extended time to achieve a 25 . 4 mm wide crack. Manual interference with the normal material volume expansion slowed the cracking process but did not truncate it, while the manufacturer's recommendation to introduce water post-cracking actually reduced and slowed the extent of cracking.

Abstruct-MOSFET's with ultrathin (5 to 8.5 nm) silicon oxynitride gate film prepared by low-pressure rapid thermal chemical vapor deposition (RTCVD) using SiH4, NzO and NH3 gases, are studied by low-frequency noise measurements (1 Hz up to 5 kHz). The analysis takes into account the correlated mobility fluctuations induced by those of the interfacial oxide charge. The nitrogen concentration, determined from SIMS analysis, varies from 0 to 11% atomic percentage. A comparison of the electrical properties between thermal and silicon oxynitride films is presented. The increasing LF noise signal with nitrogen atomic percentage indicates the presence of a higher density of slow interface traps with increasing nitrogen incorporation. Besides, a higher Coulomb scattering rate due to the nitridation induced interface charge explains reasonably well the degradation of the low field mobility after nitridation.