1,721,216 research outputs found
A quasi-analytical model for nanowire FETs with arbitrary polygonal cross section
No full textIn this work a quasi-analytical physical model has been developed for the prediction of the potential in SiNW devices with arbitrary polygonal cross section. The model is then extended to the transport direction; a method for the calculation of the natural channel length has been proposed and validated by means of 2D and 3D numerical device simulations. With the results based on the proposed model it is possible to compare nanowires with cross sections of different shape and predict the minimum technological gate length able to assure immunity to the SCEs
Underlap counterdoping as an efficient means to suppress lateral leakage in the electron–hole bilayer tunnel FET
Full text linkThe electron–hole bilayer tunnel (EHBTFET)has been proposed as a density of states (DOS)
switch capable of achieving a subthreshold slope lower than 60mV/decade at room temperature;
however, one of the main challenges is the control of the lateral band-to-band tunneling (BTBT)
leakage in the OFF state. In this work, we show that by using oppositely doped underlap regions;
the unwanted penetration of the wavefunction into the underlap region at low gate biases is
prevented; thereby drastically reducing the lateral BTBT leakage without any penalty on the ON
current. The method is verified using a full-quantum 2D Schrödinger–Poisson solver under the
effective mass approximation. For a channel thickness of 10 nm, an In0.53Ga0.47As EHBTFET
with counterdoping can exhibit an ON-current up to 20 mA mm and an average subthreshold
swing (SS) of about 30 mV/dec. Compared to previous lateral leakage suppression solutions, the
proposed method can be fabricated using template-assisted selective epitaxy
Demonstration of subthrehold swing smaller than 60mV/decade in Fe-FET with P(VDF-TrFE)/SiO2 gate stack
No full textThis work experimentally demonstrates, for the first time, that by integrating a thin ferroelectric layer into a gate stack of a standard MOS transistor one, it is possible to overcome the 60mV/decade subthreshold swing limit at room temperature of MOSFET. We find sub-threshold swings as low as 13mV/decade in Fe-FETs with 40nm P(VDF- TrFE)/SiO2 gate stack. The mechanism governing the low subthreshold swing in Fe-FET transistors is the negative capacitance of the ferroelectric layer that provides voltage amplification; with our particular ferroelectric gate stack we report for the first time negative capacitance at room temperature
A study of polarization effects in metal-ferroelectric-oxide-semiconductor capacitors
No full textIn this paper we report the fabrication and detailed electrical characterization of a Metal-Ferroelectric-Oxide-Semiconductor Capacitor aiming at the extraction of the polarization characteristic. In order to evaluate the electrical performances of the ferroelectric over SiO2 capacitor, we propose a simple device test structure featuring an intermediate contact between the two insulators. The investigated test structures are fabricated on highly doped silicon with a gate stack including 40nm silicon dioxide, 100nm Pt intermediate contact, 160nm P(VDF-TrFE) and Au as a top contact. Based on voltage measurements and using an analytical model, we subsequently extract the polarization curves without the need of capacitive measurements. The proposed test structure can serve the future experimental investigation of the possible negative capacitances in complex ferroelectric gate stacks. © 2009 IEEE.NANOLA
Metal-ferroelectric-metal-oxide-semiconductor field effect transistor with sub-60mV/decade subthreshold swing and internal voltage amplification
No full textThis work reports the first complete experimental demonstration and investigation of subthreshold swing, SS, smaller than 60 mV/decade, at room temperature, due to internal voltage amplification in FETs with a Metal-Ferroelectric-Metal-Oxide gate stack. The investigated p-type MOS transistor is a dedicated test structure to explore the negative capacitance effect by probing the internal voltage between the P(VDF-TrFE) and SiO 2 dielectric layers of the gate stack. We find that the region of internal surface potential amplification, dψ S /dV g >;1, corresponds to an S-shape of the polarization versus ferroelectric voltage (associated with negative capacitance). In Fe-FETs the internal voltage amplification could significantly lower their SS, even without reaching sub-60mV/dec values. SS min as low as 46 to 58 mV/decade and average swings, SS avg , as small as 51 to 59 mV/dec are observed for the first time in a minor loop hysteretic characteristics of Fe-FETs
An experimental study of temperature influence on electrical characteristics of ferroelectric P(VDF-TrFE) FETs on SOI
No full textWe report on the fabrication and electrical characterization of ferroelectric FETs (Fe-FET) on fully depleted SOI. The transistor gate stack is made by a 45nm P(VDF-TrFE) 70%-30% layer on top of 10nm thermal SiO2. The improved junction leakage control in thin SOl enables the accurate investigation of the electrical DC characteristics of Fe-FETs in a range of temperature from 25°C up to 90°C. Reductions of the non-saturated hysteretic loop and of lon/Ioff are observed at high temperature but the Fe-FET remarkably maintains basic switch functionality with Ion/Ioff> 105 up to 85°C. We particularly report and explain the parabolic dependence of the SOl Fe-FET subthreshold swing, SS, on the temperature, featuring an experimental minimum. ©2009 IEEE
TowardsSustainableEnterprisesinUncertainBusinessEnvironment
No full textManaging resources based on dynamic capabilities for enhancing performance could help
enterprises advance towards sustainablegrowth, solving the challenges offered by the economic
crisis and the uncertain markets. The first aim of the paper is to analyze various theoretical
approaches related to the links between the real options (ROs) concept and some important
strategicmanagementelements.Thesecondaimofthepaperistopresenttheresultsofresearch
among decision-makers from Romania regarding the management process of enterprises. The
results outline that the paper has contributions in terms of theoretical implications because it
proposes a mathematical model based on RO. The quantitative research shows that decision-
makers implementwell-knownstrategies,theyneednew instruments todeveloptheirenterprises
and they are interested in creating a strong tool based on a real options analysis and strategic
management elements. A RO application was carried out on a real organization to prove the
practicalinfluenceinthedecision-makingprocess
A model for robust electrostatic design of nanowire FETs with arbitrary polygonal cross sections
No full textIn this work a quasi-analytical physical model for the accurate prediction of the potential of GAA nanowire transistors with an arbitrary regular polygon as a cross section is developed. Two case studies concerning triangular and square cross-sections are particularly investigated and analyzed. The model is then extended to the transport direction; general expressions for the natural length are derived and validated by means of two- and three-dimensional numerical device simulations. Basic design guidelines, using an original analytical expression of the natural length, for robust electrostatic design are proposed, to predict the minimum technological gate length able to assure immunity to the SCEs
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
