9,963 research outputs found
Plangebied Waalbos, gemeenten Ridderkerk en Zwijndrecht; archeologisch vooronderzoek: een inventariserend veldonderzoek
No full textCoordinaten: 99.200/428.670
Datum einde onderzoek:22 augustus 2008, rapportage: 25 november 2008
Projectmedewerkers:drs. D. Bekius, drs. S. de Kruif, drs. R. Timmerman & W. Verschoof
Complextype(n):NX
Datering:LMEA
Diversen: Groot, R.W. de, Plangebied Waalbos, gemeenten Ridderkerk & Zwijndrecht; archeologisch vooronderzoek: een inventariserend veldonderzoek, RAAPrapport 1789 (WEESP, 2008
Asymmetric gate induced drain leakage and body leakage in vertical MOSFETs with reduced parasitic capacitance
No full textVertical MOSFETs, unlike conventional planar MOSFETs, do not have identical structures at the source and drain, but have very different gate overlaps and geometric configurations. This paper investigates the effect of the asymmetric source and drain geometries of surround-gate vertical MOSFETs on the drain leakage currents in the OFF-state region of operation. Measurements of gate-induced drain leakage (GIDL) and body leakage are carried out as a function of temperature for transistors connected in the drain-on-top and drain-on-bottom configurations. Asymmetric leakage currents are seen when the source and drain terminals are interchanged, with the GIDL being higher in the drain-on-bottom configuration and the body leakage being higher in the drain-on-top configuration. Band-to-band tunneling is identified as the dominant leakage mechanism for both the GIDL and body leakage from electrical measurements at temperatures ranging from ?50 to 200?C. The asymmetric body leakage is explained by a difference in body doping concentration at the top and bottom drain–body junctions due to the use of a p-well ion implantation. The asymmetric GIDL is explained by the difference in gate oxide thickness on the vertical (110) pillar sidewalls and the horizontal (100) wafer surface
The AM Canum Venaticorum binary SDSS J173047.59+554518.5
No full textThe AM Canum Venaticorum (AM CVn) binaries are a rare group of hydrogen-deficient, ultrashort period, mass-transferring white dwarf binaries and are possible progenitors of Type Ia supernovae. We present time-resolved spectroscopy of the recently discovered AM CVn binary SDSS J173047.59+554518.5. The average spectrum shows strong double-peaked helium emission lines, as well as a variety of metal lines, including neon; this is the second detection of neon in an AM CVn binary, after the much brighter system GP Com. We detect no calcium in the accretion disc, a puzzling feature that has been noted in many of the longer period AM CVn binaries. We measure an orbital period, from the radial velocities of the emission lines, of 35.2 ± 0.2 min, confirming the ultracompact binary nature of the system. The emission lines seen in SDSS J1730 are very narrow, although double-peaked, implying a low-inclination, face-on accretion disc; using the measured velocities of the line peaks, we estimate i ≤ 11°. This low inclination makes SDSS J1730 an excellent system for the identification of emission lines
High quality Schottky contacts for limiting leakage currents in Ge-based Schottky barrier MOSFETs
No full textSchottky barrier (SB) Ge channel MOSFETs suffer from high drain-body leakage at the required elevated substrate doping concentrations to suppress source-drain leakage. Here we show that electrodeposited Ni-Ge and NiGe/Ge Schottky diodes on highly doped Ge show low off current, which might make them suitable for SB p-MOSFETs. The Schottky diodes showed rectification of up to 5 orders in magnitude. At low forward biases the overlap of the forward current density curves for the as deposited Ni/n-Ge and NiGe/n-Ge Schottky diodes indicates Fermi-level pinning in the Ge band gap. The SB height for electrons remains virtually constant at 0.52 eV (indicating a hole barrier height of 0.14 eV) under various annealing temperatures. The series resistance decreases with increasing annealing temperature in agreement with four point probe measurements indicating the lower specific resistance of NiGe as compared to Ni, which is crucial for high drive current in SB p-MOSFETs. We show by numerical simulation that by incorporating such high quality Schottky diodes in the source/drain of a Ge channel PMOS, highly doped substrate could be used to minimize the subthreshold source to drain leakage current
Photos of Prof. Roger D. Groot, 1942-2005
No full textWhen Professor Roger Groot died suddenly in the fall of 2005 while hunting in Rockbridge County, he had served on the faculty of Washington and Lee\u27s law school for more than thirty years. This extraordinary man had influenced countless students, and their grief at his death mirrored the reaction of his colleagues in the academy and attorneys in the criminal defense bar around the country.
Brian C. Murchison from A Tribute to Roger D. Groot at 64 Wash. & Lee L. Rev. 3https://scholarlycommons.law.wlu.edu/powell_webexhibits/1012/thumbnail.jp
Design of 50nm Vertical MOSFET Incorporating a Dielectric Pocket
No full textA new architecture for a vertical MOS transistor is proposed that incorporates a so-called dielectric pocket (DP) for suppression of short channel effects and bulk punch-through. We outline the advantages that the DP brings and propose a basic fabrication process to realize the device. The design issues of a 50-nm channel device are addressed by numerical simulation. The gate delay of an associated CMOS inverter is assessed in the context of the International Technology Roadmap for Semiconductors and the vertical transistor is seen to offer considerable advantages down to the 100-nm node and beyond due to the dual channels and the ability to produce a 50-nm channel length with more relaxed lithography
Self-aligned silicidation of surround gate vertical MOSFETs for low cost RF applications
No full textWe report for the first time a CMOS-compatible silicidation technology for surround-gate vertical MOSFETs. The technology uses a double spacer comprising a polysilicon spacer for the surround gate and a nitride spacer for silicidation and is successfully integrated with a Fillet Local OXidation (FILOX) process, which thereby delivers low overlap capacitance and high drive-current vertical devices. Silicided 80-nm vertical n-channel devices fabricated using 0.5-?m lithography are compared with nonsilicided devices. A source–drain (S/D) activation anneal of 30 s at 1100 ?C is shown to deliver a channel length of 80 nm, and the silicidation gives a 60% improvement in drive current in comparison with nonsilicided devices. The silicided devices exhibit a subthreshold slope (S) of 87 mV/dec and a drain-induced barrier lowering (DIBL) of 80 mV/V, compared with 86 mV/dec and 60 mV/V for nonsilicided devices. S-parameter measurements on the 80-nm vertical nMOS devices give an fT of 20 GHz, which is approximately two times higher than expected for comparable lateral MOSFETs fabricated using the same 0.5-?m lithography. Issues associated with silicidation down the pillar sidewall are investigated by reducing the activation anneal time to bring the silicided region closer to the p-n junction at the top of the pillar. In this situation, nonlinear transistor turn-on is observed in drain-on-top operation and dramatically degraded drive current in source-on-top operation. This behavior is interpreted using mixed-mode simulations, which show that a Schottky contact is formed around the perimeter of the pillar when the silicided contact penetrates too close to the top S/D junction down the side of the pillar
The IPHAS catalogue of H alpha emission-line sources in the northern Galactic plane
No full textWe present a catalogue of point-source H alpha emission-line objects selected from the INT/WFC Photometric Ha Survey (IPHAS) of the northern Galactic plane. The catalogue covers the magnitude range 13 <= r' <= 19.5 and includes Northern hemisphere sources in the Galactic latitude range -5 degrees < b < 5 degrees. It is derived from similar to 1500 deg(2) worth of imaging data, which represents 80 per cent of the final IPHAS survey area. The electronic version of the catalogue will be updated once the full survey data become available. In total, the present catalogue contains 4853 point sources that exhibit strong photometric evidence for Ha emission. We have so far analysed spectra for similar to 300 of these sources, confirming more than 95 per cent of them as genuine emission-line stars. A wide range of stellar populations are represented in the catalogue, including early-type emission-line stars, active late-type stars, interacting binaries, young stellar objects and compact nebulae.
The spatial distribution of catalogue objects shows overdensities near sites of recent or current star formation, as well as possible evidence for the warp of the Galactic plane. Photometrically, the incidence of Ha emission is bimodally distributed in (r' - i'). The blue peak is made up mostly of early-type emission-line stars, whereas the red peak may signal an increasing contribution from other objects, such as young/active low-mass stars. We have cross-matched our H alpha-excess catalogue against the emission-line star catalogue of Kohoutek & Wehmeyer, as well as against sources in SIMBAD. We find that fewer than 10 per cent of our sources can be matched to known objects of any type. Thus IPHAS is uncovering an order of magnitude more faint (r' > 13) emission-line objects than were previously known in the Milky Way
GROOT design and components.
No full textGenerating Rhizodynamic Observations Over Time (GROOT) robot design and components. A) Photointerrupter sensors and their locations (marked with blue dots) on the GROOT system. B) NEMA 17 stepper motor. C) Openbuilds belt driven linear actuator showing NEMA 17 motor attachment with belt over the motor shaft. D) GROOT system built at Georgia Tech showing the vertical and horizontal belt driven linear actuator locations. E) Magenta 7 polycarbonate containers used for imaging. F) FLIR Flea3 Camera with GPIO cord attached to use for hardware trigger functionality. G) Dual camera setup used for GROOT with angled camera positioned above forward-facing camera.</p
Jeldert Jansz Groot: Beknopt en Getrouw Verhaal, van de Reys van Commandeur Jeldert Jansz Groot, uit Texel na en in Groenland [ca. 1779]
No full textBeknopt en Getrouw Verhaal, van de Reys van Commandeur Jeldert Jansz Groot, uit Texel na en in Groenland &c. Deszelfs Verblyf op de Kust van Oud-Groenland, naa het Verongelukken van deszelfs onderhebbend Schip, tusschen Ysland en Staatenhoek. Voorgevallen in Ao. 1777 en 1778. Gedrukt voor den Autheur, En te bekomen by de Wed. van A. van Ryschooten en Zoon, op de Haarlemmerdyk, by de Kleine Vismarkt, te Amsterdam; En by Pieter Quakkelstein, te Zaandam. [c. 1779
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