Quantum Approach To Electronic Noise Calculations In The Presence Of Electron-Phonon Interactions,
2010
Purdue University
Quantum Approach To Electronic Noise Calculations In The Presence Of Electron-Phonon Interactions, Hong-Hyun Park, Gerhard Klimeck
Birck and NCN Publications
A quantum-mechanical approach to the calculation of electronic noise for nanoscale devices is presented. This method is based on the nonequilibrium Green’s-function formalism with electron-phonon scattering mechanisms and takes the effects of the Pauli exclusion principle and the long-range Coulomb interactions into account. As examples the drain current noise characteristics of silicon nanowire transistors at room temperature are simulated. The drain current noise in the saturation regime is primarily shot-noise dominant but is suppressed for higher gate biases due to the electron-electron correlation in the channel region. The role of electron-phonon interactions on noise, the transition from thermal to shot …
Accurate Force Spectroscopy In Tapping Mode Atomic Force Microscopy In Liquids,
2010
Purdue University
Accurate Force Spectroscopy In Tapping Mode Atomic Force Microscopy In Liquids, Xin Xu, John Melcher, Arvind Raman
Birck and NCN Publications
Existing force spectroscopy methods in tapping mode atomic force microscopy (AFM) such as higher harmonic inversion [M. Stark, R. W. Stark, W. M. Heckl, and R. Guckenberger, Proc. Natl. Acad. Sci. U. S. A. 99, 8473 (2002)] or scanning probe acceleration microscopy [J. Legleiter, M. Park, B. Cusick, and T. Kowalewski, Proc. Natl. Acad. Sci. U. S. A. 103, 4813 (2006)] or integral relations [M. Lee and W. Jhe, Phys. Rev. Lett. 97, 036104 (2006); S. Hu and A. Raman, Nanotechnology 19, 375704 (2008); H. Holscher, Appl. Phys. Lett. 89, 123109 (2006); A. J. Katan, Nanotechnology 20, 165703 (2009)] require …
Molecular Modulation Of Schottky Barrier Height In Metal-Molecule-Silicon Diodes: Capacitance And Simulation Results,
2010
Purdue University - Main Campus
Molecular Modulation Of Schottky Barrier Height In Metal-Molecule-Silicon Diodes: Capacitance And Simulation Results, Adina Scott, Chad Risko, Nicholas Valley, Mark A. Ratner, David B. Janes
Birck and NCN Publications
There is considerable current interest in using molecular materials to influence the surface potential of semiconductor devices for nanoelectronic and sensing applications. We present experimental capacitance-voltage results showing that systematic Schottky barrier height modulation can be achieved using dipolar molecular layers in gold-molecule-silicon devices. A computational methodology that combines quantum chemistry and traditional electrostatic calculations is used to explore various physical effects that can influence barrier heights in such systems. Nonidealities such as silicon surface states can influence both the potential profile within the device and the validity of the extracted barrier height. Our devices exhibit low surface state densities, …
On Landauer Versus Boltzmann And Full Band Versus Effective Mass Evaluation Of Thermoelectric Transport Coefficients,
2010
Electrical and Computer Engineering, Purdue University
On Landauer Versus Boltzmann And Full Band Versus Effective Mass Evaluation Of Thermoelectric Transport Coefficients, Changwook Jeong, Raseong Kim, Mathieu Luisier, Supriyo Datta, Mark S. Lundstrom
Birck and NCN Publications
Using a full band description of electronic bandstructure, the Landauer approach to diffusive transport is mathematically related to the solution of the Boltzmann transport equation, and expressions for the thermoelectric parameters in both formalisms are presented. Quantum mechanical and semiclassical techniques to obtain from a full description of the bandstructure, E(k), the density of modes in the Landauer approach or the transport distribution in the Boltzmann solution are compared and thermoelectric transport coefficients are evaluated. Several example calculations for representative bulk materials are presented and the full band results are related to the more common effective mass formalism. Finally, given …
Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective,
2010
Purdue University - Main Campus
Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam
Birck and NCN Publications
Modern label-free biosensors are generally far more sensitive and require orders of magnitude less incubation time compared to their classical counterparts. However, a more important characteristic regarding the viability of this technology for applications in Genomics/Proteomics is defined by the ‘Selectivity’, i.e., the ability to concurrently and uniquely detect multiple target biomolecules in the presence of interfering species. Currently, there is no theory of Selectivity that allows optimization of competing factors and there are few experiments to probe this problem systematically. In this article, we use the elementary considerations of surface exclusion, diffusion limited transport, and void distribution function to …
Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques,
2010
Purdue University - Main Campus
Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Shailaja Pandit, Adri C. T. Van Duin, Ananth Y. Grama
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
Modeling atomic and molecular systems requires computation-intensive quantum mechanical methods such as, but not limited to, density functional theory (DFT) [11]. These methods have been successful in predicting various properties of chemical systems at atomistic detail. Due to the inherent nonlocality of quantum mechanics, the scalability of these methods ranges from O(N3) to O(N7) depending on the method used and approximations involved. This significantly limits the size of simulated systems to a few thousands of atoms, even on large scale parallel platforms. On the other hand, classical approximations of quantum systems, although computationally (relatively) easy to implement, yield simpler models …
Weighted Matrix Ordering And Parallel Banded Preconditioners For Iterative Linear System Solvers,
2010
Purdue University - Main Campus
Weighted Matrix Ordering And Parallel Banded Preconditioners For Iterative Linear System Solvers, Murat Manguoglu, Mehmet Koyuturk, Ahmed Sameh, Ananth Y. Grama
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
The emergence of multicore architectures and highly scalable platforms motivates the development of novel algorithms and techniques that emphasize concurrency and are tolerant of deep memory hierarchies, as opposed to minimizing raw FLOP counts. While direct solvers are reliable, they are often slow and memory-intensive for large problems. Iterative solvers, on the other hand, are more efficient but, in the absence of robust preconditioners, lack reliability. While preconditioners based on incomplete factorizations ( whenever they exist) are effective for many problems, their parallel scalability is generally limited. In this paper, we advocate the use of banded preconditioners instead and introduce …
Real-Time Monitoring Of Contact Behaviour Of Rf Mems Switches With A Very Low Power Cmos Capactive Sensor Interface,
2010
Purdue University - Main Campus
Real-Time Monitoring Of Contact Behaviour Of Rf Mems Switches With A Very Low Power Cmos Capactive Sensor Interface, Adam Fruehling, Mohammad Abu Khater, Byunghoo Jung, Dimitrios Peroulis
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
This paper presents the first ultra-low power, fully electronic methodology for real-time monitoring of the dynamic behavior of RF MEMS switches. The measurement is based on a capacitive readout circuit composed of 67 transistors with 105 µm x 105 µm footprint consuming as little as 60 µW. This is achieved by accurately sensing the capacitance change around the contact region at sampling rates from 10 kHz to 5 MHz. Experimental and simulation results show that times of not only the first contact event but also all subsequent contact bounces can be accurately measured with this technique without interfering with the …
A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors,
2010
Purdue University - Main Campus
A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors, Hao-Han Hsu, Dimitrios Peroulis
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
In this paper we present, for the ¯rst time, an experimentally-extracted model for the spring con- stant and tuning range of an analog RF-MEMS var- actor that includes viscoelastic e®ects in RF-MEMS devices. By utilizing a bi-state bias condition with one state lasting 60 minutes and the other 1 minute, this model focuses on capturing the true electrome- chanical behavior of the varactor. An experimental setup with very high long-term accuracy is created to measure capacitance of the varactor up to 1,370 hours. The impact of these e®ects and the e®ective- ness of the model are demonstrated on a tunable- …
Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators,
2010
Purdue University - Main Campus
Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators, Ajit K. Vallabhaneni, Jeffrey F. Rhoads, Xiulin Ruan, Jayathi Y. Murthy
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
This work examines the quality factors (Q factors) of resonance associated with the axial and transverse vibrations of single-wall carbon nanotube (SWCNT) resonators through the use of molecular dynamics (MD) simulation. Specifically, the work investigates the effect of device length, diameter, and chirality, as well as temperature, on the resonant frequency and quality factor of these devices, and benchmarks the results of MD simulation against classical theories of energy dissipation. Of note are the facts that the quality factors associated with transverse vibration decrease with increasing device diameter and are largely insensitive to chirality. Additionally, quality factors increase with increasing …
Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion,
2010
University of South Carolina - Columbia
Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion, C. Kuang, Wei Zhao, Guiren Wang
Faculty Publications
Stimulated emission depletion (STED) microscopy is one of the breakthrough technologies that belong to far-field optical microscopy and can achieve nanoscale spatial resolution. We demonstrate a far-field optical nanoscopy based on continuous wave lasers with different wavelengths, i.e., violet and green lasers for excitation and STED, respectively. Fluorescent dyes Coumarin 102 and Atto 390 are used for validating the depletion efficiency. Fluorescent nanoparticles are selected for characterizing the spatial resolution of the STED system. Linear scanning of the laser beams of the STED system along one line of a microscope slide, which is coated with the nanoparticles, indicates that a …
Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons,
2010
Technological University Dublin
Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath
Doctoral
Single-walled carbon nanotubes (SWCNTS) are proposed to be one of the most promising nanomaterials, with unique electronic and mechanical properties which lend themselves to a variety of applications. In all cases the quality of the SWCNT material is important, and for some applications it is paramount. Despite sustained efforts, all currently known SWCNT synthetic techniques generate significant quantities of impurities. They also grow in bundles or ropes and are largely insoluble in common organic solvents. SWCNTS can have a range of structures and their electronic properties (metallic or semiconducting) depend on their structure and as well on their diameters. Currently …
Quantum Dot Quantum Computation In Iii-V Type Semiconductor,
2010
University at Albany, State University of New York
Quantum Dot Quantum Computation In Iii-V Type Semiconductor, Sanjay K. Prabhakar
Legacy Theses & Dissertations (2009 - 2024)
Among recent proposals for next-generation, non-charge-based logic is the notion that a single electron can be trapped and spin of the electron can be manipulated through the application of gate potentials. In the thesis, there are two major contributions of the manipulation of electron spin. In regard to the first contribution, we present numerical simulations of such a spin in single electron devices for realistic asymmetric potentials in electrostatically confined quantum dot. Using analytical and numerical techniques we show that breaking in-plane rotational symmetry of the confining potential by applied gate voltage leads to a significant effect on the tuning …
Investigation Of The Threshold Voltage Shift Effect Of La2o3 On Tin/Hfo2/La2o3/Sio2/Si Stacks,
2010
University at Albany, State University of New York
Investigation Of The Threshold Voltage Shift Effect Of La2o3 On Tin/Hfo2/La2o3/Sio2/Si Stacks, Ming Di
Legacy Theses & Dissertations (2009 - 2024)
The semiconductor industry continues to scale (shrink) transistor dimensions to both increase the number of transistors per integrated circuit and their speed. One important aspect of scaling is the need to decrease the equivalent oxide thickness of the transistor gate dielectric while minimizing leakage current. Traditional thin layer SiO2 or SiOxNy films have been replaced by higher dielectric constant film stacks Here we study one example, the HfO2/La2O3/SiO2 stack. This dissertation describes an investigation of the use of La2O3 to reduce the threshold voltage of TiN/HfO2/SiO2/Si stacks (high-k/metal gate stacks). A significant aspect of this study is the determination of …
A Study Of Reticle Non-Flatness Induced Image Placement Error In Extreme Ultraviolet Lithography,
2010
University at Albany, State University of New York
A Study Of Reticle Non-Flatness Induced Image Placement Error In Extreme Ultraviolet Lithography, Sudharshanan Raghunathan
Legacy Theses & Dissertations (2009 - 2024)
As the semiconductor industry continues scaling devices to smaller sizes, the need for next generation lithography technology for fabricating these small structures has always been at the forefront. Over the past few years, conventional optical lithography technology which has adopted a series of resolution enhancement techniques to support the scaling needs is expected to run out of steam in the near future. Extreme Ultra Violet lithography (EUVL) is being actively pursued by the semiconductor industry as one of the most promising next generation lithographic technologies. Most of the issues unique to EUVL arise from the use of 13.5 nm light …
Fabrication And Characterization Of Nanomaterials Grown By Electron Beam Induced Deposition Process,
2010
University at Albany, State University of New York
Fabrication And Characterization Of Nanomaterials Grown By Electron Beam Induced Deposition Process, Juntao Li
Legacy Theses & Dissertations (2009 - 2024)
Platinum&ndash and tungsten&ndashcontaining materials were grown on bulk substrates from a variety of precursors including (CH3)3CH3C5H4Pt, W(CO)6, WF6, and Pt(PF3)4 in either a high vacuum dual beam focused ion beam/scanning electron microscope (FIB&ndashSEM) or an environmental scanning electron microscope (ESEM). The effects of deposition conditions on the growth kinetics, microstructure and composition of the grown materials, structural and chemical homogeneity of impurities inside the deposits as well as the resistivity were investigated.
Nanoabrasives Retention And Removal Mechanisms In Polyurethane Pads For Copper Cmp,
2010
University at Albany, State University of New York
Nanoabrasives Retention And Removal Mechanisms In Polyurethane Pads For Copper Cmp, Iftikhar Ul-Hasan
Legacy Theses & Dissertations (2009 - 2024)
The continued reduction in integrated circuit (IC) feature size requires similar reductions in surface defectivity. A key source of surface defects in IC fabrication processes stems from nanoabrasives used in chemical-mechanical planarization (CMP) processing. During CMP processing, polished surfaces are more vulnerable to defects including scratching, nanoabrasive particle adhesion and nanoabrasive agglomerate adhesion. The removal of these nano-sized particles is a priority for the IC fabrication industry and is reflected in the 2008 ITRS defect budget. However, there is insufficient technical understanding regarding the retention of residual nanoabrasives on the surfaces of the CMP pad following a CMP process and …
Design And Development Of Highly Active, Nanoengineered, Platinum Based Core-Shell Electrodes For Proton Exchange Membrane Fuel Cells,
2010
University at Albany, State University of New York
Design And Development Of Highly Active, Nanoengineered, Platinum Based Core-Shell Electrodes For Proton Exchange Membrane Fuel Cells, Seth Louis Knupp
Legacy Theses & Dissertations (2009 - 2024)
Highly active nanoengineered core-shell electrocatalyst have a great potential to be used as fuel cell electrodes. They can alleviate problems related with commercial carbon supported platinum by simultaneously lowering cost while enhancing reaction kinetics and overall performance. More recently, use of nanoengineered core-shell electrode structures have showed their ability to enhance the stability and overall lifetime of the catalyst without sacrificing the electrode's performance. We studied the potential of using highly active core-shell nanoparticles supported on carbon nanomaterials as fuel cell electrodes.
Nanivid : A New Research Tool For Tissue Microenvironment Studies,
2010
University at Albany, State University of New York
Nanivid : A New Research Tool For Tissue Microenvironment Studies, Waseem Khan Raja
Legacy Theses & Dissertations (2009 - 2024)
Metastatic tumors are heterogeneous in nature and composed of subpopulations of cells having various metastatic potentials. The time progression of a tumor creates a unique microenvironment to improve the invasion capabilities and survivability of cancer cells in different microenvironments. In the early stages of intravasation, cancer cells establish communication with other cell types through a paracrine loop and covers long distances by sensing growth factor gradients through extracellular matrices. Cellular migration both in vitro and in vivo is a complex process and to understand their motility in depth, sophisticated techniques are required to document and record events in real time. …
Nano-Scaled Fet Device For Cmos Technology,
2010
North Carolina Agricultural and Technical State University
Nano-Scaled Fet Device For Cmos Technology, Prabhat Ranjan Pathak
Dissertations
In this work the 3-D structure of the Accumulation mode (ACM) and Enhance mode (ECM) FinFET was developed by the Taurus-Device Editor. The design of both ACM and ECM FinFET was optimized for high-performance IC applications to meet ITRS specification for Ioff current, for 9nm gate length. The design of ACM and ECM FinFET is optimized, analyzed and compared against each other with respect to Darin Induced Barrier Lower (DIBL), Sub-threshold Swing(SS), operation and performance characteristics with varying electrical and physical parameters Silicon thickness (Tsi), Source/Drain doping gradient (σsd), electrical channel length (Leff ), …
