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Multiple turbidity currents were recorded in two submarine canyons with maximum speed as high as 280 cm/s. For each individual turbidity current measured at a fixed station, its depth-averaged velocity typically decreased over time while its thickness increased. Some turbidity currents gained in speed as they traveled downcanyon, suggesting a possible self-accelerating process. The measured velocity profiles, first in this high resolution, allowed normalizations with various schemes. Empirical functions, obtained from laboratory experiments whose spatial and time scales are two to three orders of magnitude smaller, were found to represent the field data fairly well. The best similarity collapse of the velocity profiles was achieved when the streamwise velocity and the elevation were normalized respectively by the depth-averaged velocity and the turbidity current thickness. This normalization scheme can be generalized to an empirical function Y = exp(-[alpha][X.sup.[beta]]) for the jet region above the velocity maximum. Confirming theoretical arguments and laboratory results of other studies, the field turbidity currents are Froude-supercritical. doi: 10.1130/G30582.1

A physical model on remote interface-roughness scattering (RIRS) and remote Coulomb scattering (RCS) in SiGe p-MOSFETs with high-k dielectric/interlayer gate-stacked structure is presented. The permittivity of the high-K dielectric has opposite effects on the RCS and RIRS-limited mobilities.

Dynamic-stress-induced enhanced degradation of 1/frequency noise has been investigated in n-MOSFETs with thermal oxide or nitrided oxide as the gate dielectric. Physical mechanisms were analyzed. Degradation of 1/frequency noise under ac stress was found to be far more significant than that under dc stress. Under the two types of ac stress conditions, much smaller degradation of 1/frequency noise is seen for the nitrided device because of the improved oxide/Si interface and near-interface oxide factors associated with interfacial nitrogen .

The authors present designs for a high-quality thin gate dielectric transistor. Topics include hot-carrier stress, MOS devices, and oxynitrides.

The role of degradation in increasing 1/f noise in n-channel metal-oxide-semiconductor field-effect transistors subjected to various hot-carrier stresses has been studied. Results indicate that the rise in 1/f noise can be traced to greater carrier-number fluctuations from oxide traps under any hot-carrier stress. For maximum substrate- and gate-current stresses, 1/f noise results from enhanced surface-mobility fluctuation due to electron trapping at preexisting and generated fast interface states.

An experiment was conducted to determine the accuracy of charge-pumping measurement technique with gate sawtooth pulses on metal oxide semiconductor field effect transistors. A pulse generator was utilized to supply the gate sawtooth pulses and a reverse bias method was applied to the source and drain of the transistors. Results revealed that the dominant mechanism which affected the measurement accuracy was the energy range of interface-trap distribution.

A trap assisted, two-step tunneling model is developed and used to investigate the relation of increased interface states in n-MOS field effect transistors to post-stress, gate-induced-drain-leakage (GIDL) current increase during hot-carrier stress. It will be shown that the two-step tunneling method is so dominant under appropriate drain-gate biases that GIDL current shift is insensitive to temperatures up to about 50 degrees centigrade.

A study using backsurface argon bombardment has been carried out on interface and charge-trapping properties of nitrided n-channel metal-oxide-semiconductor field-effect transistors (n-MOSFETs). After bombardment, interface state density lessens and interface hardness against hot-carrier bombardment gets better. Oxide-charge-trapping properties were better. Turnaround behavior could be seem in the improvements depending on bombardment conditions. It can be attributed to stress compensation in the area of the Si/SiO(sub.2) interface and annealing effects.

A study was conducted on the design and properties of two superconducting tubular linear induction motors. One of the motors features NBbTi superconducting primary windings and the other has oxide superconducting primary windings. Finite element analysis reveals that the oxide motor has a starting thrust of 22.9 N at 4000 ampere turns per phase while the NbTi motor's starting thrust is 15.4 N at 4000 ampere turns per phase.