5,414 research outputs found
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
Diversity of secondary metabolites from Genus Artocarpus (Moraceae)
No full textAbstrak. Hakim A. 2010. Keanekaragaman metabolit sekunder Genus Artocarpus (Moraceae). Nusantara Bioscience 2:146-156.
Beberapa spesies dari genus Artocarpus (Moraceae) telah diteliti kandungan bahan alamnya. Metabolit sekunder yang berhasil diisolasi
dari genus Artocarpus terdiri dari terpenoid, flavonoid, stilbenoid, arilbenzofuran, neolignan, dan adduct Diels-Alder. Kelompok
flavonoid merupakan senyawa yang paling banyak ditemukan dari tumbuhan Artocarpus. Senyawa flavonoid yang telah berhasil
diisolasi dari tumbuhan Artocarpus memiliki kerangka yang beragam seperti calkon, flavanon, flavan-3-ol, flavon sederhana,
prenilflavon, oksepinoflavon, piranoflavon, dihidrobenzosanton, furanodihidrobenzosanton, piranodihidrobenzosanton, kuinonosanton,
siklolopentenosanton, santonolid, dihidrosanton.
Kata kunci: Artocarpus, Moraceae, flavonoid, Diels-Alder, metabolit sekunder
Population Policy Shifts and Their Implications for Population Stabilisation in Pakistan
No full textThe visible fast increase in the growth rate of world population occurred during the second half of the twentieth century due to the faster declines in mortality following the medical and public health advances made around the time of World War II. The global population growth rate after peaking of at around 1.7 to 1.9 percent per annum in the 1970s and 1980s has since started declining and is currently around 1.4 percent per annum. The world population more than doubled, recording 142 percent increase, from 2.51 billion in 1950 to around 6.07 billion in 2000 [Hakim (2000)]. Most of the increase has been in less developed countries, from 1.68 billion in 1950 to 4.88 billion in 2000, recording 190 percent. Compared to this, the more developed countries witnessed only a marginal increase of 43 percent from 0.83 billion in 1950 to 1.19 billion population in 2000.
Computationally efficient quantum-mechanical technique to calculate direct tunnelling gate leakage current in metal-oxide-semiconductor structures
No full textWe propose a computationally efficient, accurate and numerically stable quantum- mechanical technique to calculate the direct tunneling (DT)gate current in metal-oxide-semiconductor (MOS) structures. Knowledge of the imaginary part G of the complex eigenenergy of the quasi-bound inversion layer states is required to estimate the lifetimes of these states. Exploiting the numerically obtained exponential dependence of G on the thickness of the gate-dielectric layer even in the sub-1-nm-thickness regime, we have simplified the determination of G in devices where it is too small to be calculated directly. It is also shown that the MOS electrostatics, calculated self-consistently with open boundary conditions, is independent of the dielectric layer tickness provided that the other parameters remain unchanged. Utilizing these findings, a computationally efficient and numerically stable method is developed for calculating the tunneling current–gate voltage characteristics. The validity of the proposed model is demonstrated by comparing simulation results with experimental data. Sample calculations for MOS transistors with high-K gate-dielectric materials are also presented. This model is particularly suitable for DT current calculation in devices with thicker gate dielectrics and in device or process characterization from the tunneling current measurement
William L. Neumann. Making the Peace (1941-1945)
No full textHakim Henry. William L. Neumann. Making the Peace (1941-1945). In: Politique étrangère, n°4 - 1950 - 15ᵉannée. pp. 467-470
Improved sub-threshold Slope in RF vertical MOSFETS using a frame gate architecture
No full textWe report a CMOS-compatible vertical MOSFET, which incorporates a frame gate architecture suitable for application in RF circuits. Fabricated surround gate vertical MOSFETs with the frame gate architecture show no degradation of short channel effects when the channel length is scaled, while control devices show significantly degraded sub-threshold slope and DIBL. The frame gate vertical MOSFETs show near ideal sub-threshold slopes of 70-80mV/decade and DIBL of 30-35mV/V in a 100 nm gate length nMOS device. In contrast, the control vertical MOSFETs without the frame gate exhibit sub-threshold slopes of 110 to 140 mV/decade and DIBL of 100 to 280 mV/V. This improved sub-threshold slope is explained by the elimination of etch damage during gate etch
Improved sub-threshold slope in short channel vertical MOSFETs using FILOX oxidation
No full textThis paper investigates the origins of sub-threshold slope degradation in vertical MOSFETs (v-MOSFETs) due to dry etching of the polysilicon surround gate. Control v-MOSFETs exhibit a degradation of sub-threshold slope as the channel length is reduced from 250 to 100 nm, with 100 nm transistors having a value of 125 mV/dec and a DIBL of 210 mV/V. The effect of the polysilicon gate etch is investigated using a frame-gate architecture in which the polysilicon gate overlaps the side of the pillar, thereby protecting the channel from etch damage. This device shows no degradation of short channel effects when the channel length is scaled and exhibits a near-ideal sub-threshold slope of 76 mV/dec and a DIBL of 33 mV/V at a channel length of 100 nm. Gated diode measurements unambiguously demonstrate that this improved sub-threshold slope is due to the elimination of etch damage at the top and bottom of the pillar created during polysilicon gate etch. An alternative method of eliminating dry etch damage is then investigated by optimizing the Fillet Local Oxidation (FILOX). These devices give a sub-threshold slope of 81 mV/dec and a DIBL of 25 mV/V at a channel length of 100 nm. The improved immunity to dry etch damage is due to the creation of a thick protective oxide at the top and bottom of the pillar during the FILOX proces
Development of musical listening in curricular and extracurricular practices of composition and arrangement students
No full text“Soy profesora de Música de una asignatura llamada Formación Auditiva”, nos dice Genoveva Salazar Hakim en el comienzo del libro. Este es el punto de partida desde el cual se embarca en un recorrido por esas tensiones que va dejando al descubierto, sus orígenes, causas, desarrollos y consecuencias. El territorio andado es el de la formación auditiva, un espacio paradojal y caleidoscópico, en el cruce de las exigencias del dominio de la notación musical de los músicos del siglo
XIX y las necesidades que de ella tienen los protagonistas de la cultura musical posalfabetizada. Personalmente, comparto con ella este campo profesional y puedo decir que tal vez sea este uno de los espacios académico-musicales que más bestial
e inexplicablemente genera adhesiones, frustraciones, sumisiones, estigmatizaciones, violencias y renunciamientos. La mirada con la que Genoveva realiza este viaje es francamente la de una docente sensible, atenta, crítica e inteligente, preocupada sin reservas por sus estudiantes, en cuanto seres sensibles y creativos, su desarrollo musical y sus vínculos con la cultura. Por ello, el objeto de estudio aquí es claramente esa sensibilidad, relatada por sus propios portadores. Aquí la autora
se muestra profundamente comprometida con el universo que investiga. No se viste con trajes antisépticos a fin de no contaminarse; por el contrario, se interesa profundamente por la suerte de las personas y las instituciones que analiza y plantea su trabajo como parte de su compromiso por su bienestar.“I am a Music teacher of a subject called Auditory Training,” Genoveva Salazar Hakim tells us at the beginning of the book. This is the starting point from which it embarks on a journey through those tensions that reveal their origins, causes, developments and consequences. The territory covered is that of auditory training, a paradoxical and kaleidoscopic space, at the crossroads of the demands of the mastery of musical notation of the musicians of the century.
XIX and the needs that the protagonists of the post-literate musical culture have. Personally, I share this professional field with her and I can say that perhaps this is one of the most brutal academic-musical spaces.
and inexplicably generates adhesions, frustrations, submissions, stigmatizations, violence and renunciations. The view with which Genoveva makes this journey is frankly that of a sensitive, attentive, critical and intelligent teacher, unreservedly concerned about her students, as sensitive and creative beings, their musical development and their links with culture. Therefore, the object of study here is clearly that sensitivity, reported by its own bearers. Here the author
She is deeply committed to the universe she investigates. He does not dress in antiseptic suits in order not to become contaminated; On the contrary, he is deeply interested in the fate of the people and institutions he analyzes and presents his work as part of his commitment to their well-being.Bogot
Improved drive current in RF vertical MOSFETS using hydrogen anneal
No full textThis letter reports a study on the effect of a hydrogen anneal after silicon pillar etch of surround-gate vertical MOSFETs intended for RF applications. A hydrogen anneal at 800 ?C is shown to give a 30% improvement in the drive current of 120-nm n-channel transistors compared with transistors without the hydrogen anneal. The value of drive current achieved is 250 ?A/?m, which is a record for thick pillar vertical MOSFETs. This improved performance is obtained even though a sacrificial oxidation was performed prior to the hydrogen anneal to smooth the pillar sidewall. The values of subthreshold slope and DIBL are 79 mV/decade and 45 mV/V, respectively, which are significantly better than most values reported in the literature for comparable devices. The H2 anneal is also shown to decrease the OFF-state leakage current by a factor of three
Role of aquaporins in the cell signalling mediated by hydrogen peroxide in leukemic cells
No full textRole of aquaporins in the cell signalling mediated by hydrogen peroxide in leukemic cells
F. Vieceli Dalla Sega, C. Prata, C. Caliceti, L. Zambonin, D. Fiorentini, G. Hakim, L. Landi
Department of Biochemistry “G. Moruzzi”, University of Bologna, Bologna, Italy
Aquaporins (AQP) constitute a large family of integral membrane proteins, present in all domains of life, that form pores appearing to be designed for the selective passage of water and glycerol [1]. Hydrogen peroxide has been long thought to be freely diffusible but recent evidence suggest that specific mammalian aquaporin homologues (AQP8) possess the capacity to channel H2O2 across membranes [2,3]. Moreover, it has been recently shown that human cells AQP3 expression can modulate the intracellular level of H2O2 and is required for NOX-derived H2O2 signalling [3]. Redox deregulation of proliferative pathways involving ROS (particularly H2O2) in cancer initiation and progression is now firmly established. Here we tested the hypothesis that specific isoforms of aquaporins regulate the level of intracellular H2O2 produced by NOX affecting downstream pathways linked to cell proliferation. In the present study, we show that in different leukemic cell lines NOX2 and/or NOX4 are expressed and are necessary to produce ROS that, in turn, are able to sustain glucose uptake and cell proliferation. Furthermore, we report that inhibition of aquaporins diminishes intracellular ROS accumulation either when H2O2 is produced by Nox enzymes or when is added exogenously to the medium. Finally, we observe a decrease in glucose transport following aquaporins inhibition. Taken together data suggest that aquaporins can regulate hydrogen peroxide uptake and downstream pathways mediated by H2O2
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