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We have developed a real-time moment tensor monitoring system (RMT) which takes advantage of a grid-based moment tensor inversion technique and real-time broad-band seismic recordings to automatically monitor earthquake activities in the vicinity of Taiwan. The centroid moment tensor (CMT) inversion technique and a grid search scheme are applied to obtain the information of earthquake source parameters, including the event origin time, hypocentral location, moment magnitude and focal mechanism. All of these source parameters can be determined simultaneously within 117 s after the occurrence of an earthquake. The monitoring area involves the entire Taiwan Island and the offshore region, which covers the area of 119.3°E to 123.0°E and 21.0°N to 26.0°N, with a depth from 6 to 136 km. A 3-D grid system is implemented in the monitoring area with a uniform horizontal interval of 0.1° and a vertical interval of 10 km. The inversion procedure is based on a 1-D Green's function database calculated by the frequency–wavenumber (fk) method. We compare our results with the Central Weather Bureau (CWB) catalogue data for earthquakes occurred between 2010 and 2012. The average differences between event origin time and hypocentral location are less than 2 s and 10 km, respectively. The focal mechanisms determined by RMT are also comparable with the Broadband Array in Taiwan for Seismology (BATS) CMT solutions. These results indicate that the RMT system is realizable and efficient to monitor local seismic activities. In addition, the time needed to obtain all the point source parameters is reduced substantially compared to routine earthquake reports. By connecting RMT with a real-time online earthquake simulation (ROS) system, all the source parameters will be forwarded to the ROS to make the real-time earthquake simulation feasible. The RMT has operated offline (2010–2011) and online (since January 2012 to present) at the Institute of Earth Sciences (IES), Academia Sinica (http://rmt.earth.sinica.edu.tw). The long-term goal of this system is to provide real-time source information for rapid seismic hazard assessment during large earthquakes. [ABSTRACT FROM AUTHOR]

Abstract: We estimate the effects of random discrete dopants (RDs) and random interface traps (ITs) on physical and electrical characteristic fluctuations of 16-nm-gate high-κ/metal gate (HKMG) metal–oxide-semiconductor field effect transistors (MOSFETs). Two-dimensional (2D) random ITs at the hafnium oxide (HfO2)/silicon interface and 3D RDs inside the silicon channel of the 16-nm-gate HKMG MOSFETs are simultaneously incorporated into an experimentally validated 3D device simulation to quantify the RDs-and-ITs-fluctuated characteristics. The random effect of the combined RDs and ITs induces rather different fluctuation in the threshold voltage, the on-/off-state current, and the gate capacitance in the 16-nm-gate HKMG MOSFETs. The surface potential, DC and AC characteristic fluctuations are affected to different extents by the random combinatorial RDs and ITs. Nonlinearly correlated RDs and ITs violate the statistical assumption of independent identical distributions between the RDs- and ITs-induced random variables. Consequently, for the studied 16-nm-gate HKMG N-MOSFETs, the threshold voltage fluctuation induced by the combined RDs and ITs is 11% less than their statistical sum due to local interaction of surface potentials resulting from the RDs and ITs simultaneously. Similarly, it is about 8.9% for the P-MOSFET devices. Depending upon random position and number of the combined RDs and ITs, overestimation or underestimation between the statistical sum of variances and the 3D device simulation is also observed for the drain current and the gate capacitance. [Copyright &y& Elsevier]

In this paper, we estimate the effect of random work function (WK) on the threshold voltage fluctuation (\sigma Vth) of 16-nm-gate metal-oxide-semiconductor field-effect transistors (MOSFETs) with metal-gate materials. To examine the random WK induced \sigma Vth, nanosized metal grains with different gate materials are considered in a large-scale statistical simulation. An analytical expression of the WK induced \sigma Vth is proposed based on the Monte Carlo simulation results which can outlook different extents of fluctuation resulting from various metal gates and benefit the device fabrication. Devices with a two-layer metal-gate are further studied for fluctuation suppression; the finding of this paper indicates the first layer of the gate structure plays the most significant role in the suppression of the WK induced \sigma Vth, compared with the second layer. This paper provides an insight into random work-function-induced threshold voltage fluctuation, which can, in turn, be used to assess metal gate characteristics of MOSFETs. [ABSTRACT FROM PUBLISHER]

Abstract: Impact of the intrinsic fluctuations on device characteristics, such as the threshold voltage (V th) fluctuation is crucial in determining the behavior of nanoscale semiconductor devices. In this paper, the dependency of process-variation and random-dopant-induced V th fluctuation on the gate oxide thickness scaling in 16nm metal–oxide–semiconductor field effect transistors (MOSFETs) is investigated. Fluctuations of the threshold voltage for the studied planar MOSFETs with equivalent oxide thicknesses (EOT) from 1.2nm to 0.2nm (e.g., SiO2 for the 1.2 and 0.8nm EOTs, Al2O3 for the 0.4nm EOT and HfO2 for the 0.2nm EOT) are then for the first time compared with the results of 16nm bulk fin-typed filed effect transistors (FinFETs), which is one of the promising candidates for next generation semiconductor devices. An experimentally validated simulation is conducted to investigate the fluctuation property. Result of this study confirms the suppression of V th fluctuations with the gate oxide thickness scaling (using high-κ dielectric). It is found that the immunity of the planar MOSFET against fluctuation suffers from nature of structural limitations. Bulk FinFETs alleviate the challenges of device’s scaling and have potential in the nanoelectronics application. [Copyright &y& Elsevier]