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Rapid development of a well controlled manufacturing process is a key component of marketplace success. Accomplishing this requires a thorough understanding of the effects of process variations on parametric yield. Use of Technology Computer Assisted Design (TCAD) simulations and statistical analysis can decrease the time needed to assess the manufacturability of various transistor design options, and identify the key process parameters that cause the largest variations. This paper covers a new methodology that combines Design of Experiments (DOE) with process and device simulations to generate transistor parametric statistical models. Monte-Carlo simulations are performed to generate transistor parametric sensitivities and statistical distributions. Examples of applying this methodology to 130nm technology will be given.

This paper presents a transistor optimization methodology tailored for wireless, digital consumer, and mobile applications that employ power management circuit techniques. This methodology is applied to a 65nm technology that supports a high-density (

In this work, we present a 60 nm gate length CMOS for high performance applications at the 0.13 /spl mu/m CMOS node. The technology utilizes 193 nm gate lithography, dual spacers with thin spacer before drain extension implant and L-shaped nitride spacer after drain extensions, and remote-plasma nitrided dielectric with 1.75 nm EOT. 10-15% improvement in drive current is achieved with lower series resistance by reduction of dopant loss and higher dopant activation, resulting in n- and pMOS I/sub drive/ of 1160 /spl mu/A//spl mu/m and 550 /spl mu/A//spl mu/m at 1.3 V at I/sub off/=100 nA//spl mu/m.

The limitations of implementing low leakage schemes and their application to current state of the art components is discussed In addition to source subthreshold leakage, both gate induced diode leakage current and tunneling gate leakage current must be comprehended A viable leakage reduction strategy requires extensive modeling of circuits in the standby mode as well as new demands on the understanding of transistor physics. The ramifications of the physics of the behavior of transistors under conditions of high electric fields apply not only at the circuit level but can also impact the chip level system. In the coming applications of mobile electronics, understanding of this concept is critical.

A BiCMOS current source reference network which eliminates the impact of DC power supply voltage drops on the operation of ECL (emitter coupled logic) circuits is described. This is essential for implementing ECL design techniques in ULSI BiCMOS circuits. Using the current source network, reference voltages are generated locally, so that the ECL voltage references are correctly referenced to the local power supply potentials. A power-supply-insensitive bandgap reference generator is used to generate precision on-chip voltage references and current sources. The bandgap reference circuit uses both MOS and bipolar transistors and is much simpler than a similar design using bipolar-only circuitry. The micrograph of the test chip containing the bandgap circuit nd BiCMOS op amp analog drivers is shown. The drivers are designed for multiple-reference-level regeneration. The test chip has been fabricated using a 0.8- mu m BiCMOS process. The typical characteristics of the bandgap circuit and the analog driver are shown. >

A 1-Mb*1 BiCMOS ECL (emitter-coupled-logic) I/O SRAM (static random access memory) is fabricated using a 0.8- mu m BiCMOS process. This memory device utilizes a 76- mu m/sup 2/ full-CMOS six-transistor memory cell, a dual-MOS current-source BiCMOS bit line sensing scheme, a BiCMOS current-source voltage reference network, and a low-capacitance load block line decoding circuit to achieve 8-ns access time. The configurable memory array size architecture allows for memory sizes from 64 kb up to 1 Mb in 64 kb increments with no change in the peripheral circuits. The six-transistor cell layout is shown, and the memory block architecture is illustrated. The low dependence of power supply current on the operating frequency shows the impact of ECL circuits in the design. Characteristics of the SRAM are summarized. >

The authors describe a 0.5- mu m BiCMOS technology for high-performance logic and SRAMs (static RAMs) which is capable of supporting 5-V hot-carrier-hard circuit designs. In these designs the maximum drain-to-source voltage across a 0.5- mu m NMOS device is restricted to 4 V to ensure hot carrier reliability using 12-nm gate oxide. However, for the bipolar device, isolation and longer channel MOS devices, the process is required to support 5 V. For a 5-V supply voltage, the capacitive load drive factor for a BiCMOS NAND gate is 160 ps/pF, which is 30% smaller than the load drive factor for the same basic design gate built using an 0.8- mu m process with 20-nm gate oxide. The authors also discuss how a vertical NMOS driver transistor and a polysilicon PMOS load device are integrated into the 0.5- mu m BiCMOS process. The addition of these components permits a 23- mu m/sup 2/ stacked 6-T CMOS SRAM cell to be realized, suitable for 4-Mb-class BiCMOS SRAMs. >

We present the first integrated simulation and modeling approach for the silicide-source/drain structure, and for the silicide-diffusion contact resistance; thus, providing the critical link between electrical performance and the processing/structural variables forming the silicide source/drain region. We apply this approach to predict the silicide-diffusion contact resistance accurately, and to improve transistor performance significantly.

This paper presents the results of an investigation of late Holocene deposits on the Belgian coastal plain. The upper clastic deposits overlying the uppermost intercalated peat bed were studied on the basis of lithology, radiocarbon dates and foraminiferal assemblages to determine why silting-up phases or peat beds are lacking, and to establish the evolution of the sedimentary environments as well as the age of the deposits. Two contrasting sites, in quite different locations and showing a different stratigraphy, were studied. It appears that the coastal evolution was not gradual and continuous, but characterised by short periods with high-energy conditions alternating with long periods where low-energy conditions and little sedimentation prevailed. The evolution is determined mainly by tidal channel activity. At about 3400 cal. yr BP, the peat was eroded in narrow zones by the main tidal channels and this until the landward limit of the plain. The peat was only partly flooded and mudflats fringed the channels. With time, new tributaries formed and the channel network progressively enlarged. The channels were rapidly filled, followed by a period of little sedimentation, which lasted at least until 1400–1200 cal. yr BP. The following channel activity is characterised by lateral sedimentation, rather than vertical erosion, together with increased sediment reworking. The mechanisms of coastal change in the late Holocene might be similar over the entire plain, but the timing of the changes is certainly not. Copyright © 2002 John Wiley & Sons, Ltd.

The study of sedimentological features, foraminifera and molluscan fauna in samples recovered from four rotary boreholes permitted, after 14C dating, the first assessment of the post-glacial transgression in Guadiana River Estuary. The Holocene sequence is underlain by coarse sediments from delta fan enclosing continental swamp deposits dated 16980 year BP. The Holocene sedimentary sequence was deposited either directly on this delta fan gravels or on top of fluvial sands deposited probably between 11000 and 10000 yr BP. An accelerated phase of the estuary infilling by clayey sediments containing the saltmarsh foraminifer Trochammina, began ca. 9800 year BP, when sea level was about 39 m below present. Between 7500 and 7000 year BP, the central part of the estuary started to accommodate coarser sediments, partially introduced from the continental shelf. The first phase of Holocene sea-level rise at a rate of 0.85 m/century terminated ca. 6500 year BP. Since then, lagoonal sediments in the vicinity of the estuary have been enclosed behind sand spits and predominantly sandy sedimentation was initiated within the estuary. After a second phase of slower rise at the rate of 0.3 m/century, which lasted until ca. 5000 year BP, the sea approached the present level. INTERREG II programme, DISIPOL Project (Sediment Dynamics and Pollutant Dissipation in Guadiana River Estuary)

Foraminifera and thecamoebians are highly sensitive to environmental stress (natural or anthropogenic). This feature means that they can be used to biologically characterize a variety of freshwater and coastal marine environments. Due to their small size and hard shells, large quantities are also found fossilised in core samples, making them ideal for reconstructing past environmental conditions. This volume covers the specific environmental applications of these organisms and contains an introduction to the subject, detailed descriptions of methods and techniques and case studies. Written for non-specialists, this book will appeal to resource managers and consultants in the public and private sector who routinely work on coastal environmental problems. The book will also serve as a supplementary text for graduate students in many courses on environmental monitoring, ecological baseline studies and environmental science.

A glossary and some basic taxonomy on all of the species used in this book have been provided, as an appendix, for those readers who want to go a step further. The bibliography is also in the appendix and includes all the text references as well as those only in the taxonomy section of the appendix; this should provide a good literature base for further study. A variety of applications have been shown here, such as: Climatic (including sea-level) Pollution impact, monitoring, mitigation Seismic activity “fingerprints” Sediment transport phenomena (tracers) Storm activity tracers Paleoproductivity indicators Classification and characterisation of estuaries Freshwater–marine transitions There are also remarks on several other subjects. Biostratigraphy, which is the most widely known of all microfossil applications, has been excluded as it was felt that it has been already documented in great detail elsewhere; the type of applications discussed in this book represent the future of micropaleontology and will likely be the most often used in the coming decades. It is clear that there are almost as many applications for microfossils as there are environmental problems. The authors have discussed a few examples derived from their own experience, but new types of problems arise almost daily. The readers of this book should consider these examples as just that – examples – whereas the techniques discussed in the book can be applied to any type of problem that may be encountered in aquatic environments.

John S. Bradshaw died on March 25, 2010 after a long battle with the oceanographer’s disease, skin cancer; he was 82. With a degree in chemistry from San Diego State University, Jack completed his doctorate at the University of California, Los Angeles (UCLA), and then assumed post-doctoral research at Scripps Institute of Oceanography (SIO) in La Jolla. He was one of the five Martin Johnson “students” at SIO who, in the late 1950s, established the field of pelagic ecological biogeography. They found that large-scale, ocean-wide species patterns of major …

A highstand of relative sea level occurred at 4 2 ka in Murrells Inlet on the northern coast of South Carolina The highstand was followed by a sea level fall of 2 m until 3 6 ka and then a slow steady sea level rise of 10 cm century to the present Although a mid Holocene highstand has been suggested by others it has not been well constrained Strong differential submergence between Murrells Inlet and Santee Delta South Carolina has occurred over the last 4 ka probably as a result of sediment loading by and subsidence of the Santee Delta system The occurrence of the 4 2 ka highstand corresponds to the range 7 4 ka of the mid Holocene Hypsithermal The rate and magnitude of the relative sea level fluctuation are similar to those projected for future flooding and suggest that evaluation of the Hypsithermal highstand may provide an insight to projected greenhouse effect related change for the future indicate that such an event may have been a highly local ized rise in relative sea level or that the evidence of the fluctuation was destroyed by coastal processes The record of the mid Holocene relative sea level oscillation in South Carolina was limited to a small local tidal marsh system where the deposits had not yet been reworked by creeks Reworking of sequences containing relative sea level rec ords has hampered efforts to produce detailed mid to late Ho ocene relative sea level histories at other sites The Ho locene record on the adjacent shelf of North Carolina and South Carolina is poorly preserved Hine and Snyder 1985 Preservation of deposits recording detailed relative sea level changes is also limited within relatively protected coastal systems Gayes and Bokuniewicz 1991 In this paper we present a relative sea level curve from tidal wetland deposits of Murrells Inlet South Carolina that documents a mid Holocene relative sea level highstand A second data set from the Santee River Delta shows differ ential Holocene submergence along the coast that may have resulted from sediment loading by the Santee Delta

A large body of information exists on marsh foraminifera of North America but until now few quantitative studies had been done at corresponding latitudes in the southern hemisphere. To remedy this situation, we sampled six marshes along the eastern coast of South America from Tierra del Fuego (54°S) to Guaratuba, Brazil (25°S). The southernmost area corresponds in latitude to work done in Hudson-James Bay marshes and the South American material is almost identical to Hudson-James Bay with Polysaccammina ipohalina and Trochammina macrescens dominating. Marshes in between are more similar to the Californian marshes with Trochammina inflata dominating high marsh areas. In the Brazilian marsh, which is in the southernmost limit of mangroves, the fauna is similar to that found in the Mississippi Delta marshes, at approximately the same latitude north. Species here include Haplophragmoides wilberti and Arenoparrella mexicana. This study illustrates that marsh foraminifera do respond to latitudinal gradients in both hemispheres of the Americas.

Thecamoebians in general, and the superfamily Arcellacea in particular, seem ideally suited as paleolimnological tools. The scarcity of baseline biogeographical studies, however, severely limits their value as modern analogs for paleoecological reconstructions. A comparison of the modern arcellacean fauna studied from four lakes from Baffin Island (63°N), Nova Scotia (45°N), Virginia (38°N) and southern Florida (27°N) with the information available in the literature shows how several trends in arcellacean distribution exist in eastern North America.

Four foraminiferal species and nine species of arcellaceans (thecamoebians) are documented from fresh and salt-water marshes, salt flats, and salt springs in the vicinity of Lake Winnipegosis, Manitoba. As this region was never in contact with the ocean, the close similarity of the foraminiferal fauna to marsh assemblages inhabiting coastal James and Hudson Bays suggests colonization via avian transport. The replacement of a Cribroelphidium gunteri dominated fauna in the area by a Jadammina macrescens dominated fauna during the last 5000 years may have been the result of climatic deterioration and/ or a change in the migratory pattern of birds. Large numbers of Glomospira sp., found at only a single locality, are not readily referable to any known species. These specimens are either ecophenotypic variants of a coastal Glomospira species or they may represent a new species.

A RAM which uses circuit techniques and architectural innovation to achieve the performance demanded by today's systems is described. An input buffer/level translator, a current sense amplifier, and a high-speed architecture are used in this RAM to achieve the 5-ns access time along with the 0.6-mm BiCMOS technology. The chip is organized as 128 K-wordst8-b wide using a 4T2R memory cell of 28 mm2

Some basic facts concerning the biology, ecology and taxonomic problems of thecamoebians are reviewed and summarized on the assumption that this information is useful for the palaeontological applications of this group.