A novel integrated modeling methodology for NEMS is presented. Nano scale device models include typical effects found, at this scale, in various domains. The methodology facilitates the insertion of quantum corrections to nanoscale device models when they are simulated within multi-domain environments, as is performed in the MEMS industry. This methodology includes domain-oriented approximations from ab-initio modeling. In addition, the methodology includes the selection of quantum mechanical compact models that can be integrated with basic electronic circuits or non-electronic lumped element models. Nanoelectronic device modeling integration in mixed signal systems is reported. The modeling results are compatible with standard hardware description language entities and building blocks. This methodology is based on the IEEE VHDL-AMS, which is an industry standard modeling and simulation hardware description language. The methodology must be object oriented in order to be shared with current and future nanotechnology modeling resources, which are available worldwide. In order to integrate them inside a Learning Management System (LMS), models were formulated and adapted for educational purposes. The electronic nanodevice models were translated to a standardized format for learning objects by following the Shareable Content Object Reference Model (SCORM). The SCORM format not only allows models reusability inside the framework of the LMS, but their applicability to various educational levels as well. The model of a molecular transistor was properly defined, integrated and translated using SCORM rules and reused for educational purposes at various levels. A very popular LMS platform was used to support these tasks. The LMS platform compatibility skills were applied to test the applicability and reusability of the generated learning objects. Model usability was successfully tested and measured within an undergraduate nanotechnology course in an electrical engineering program. The model was reused at the graduate level and adapted afterwards to a nanotechnology education program for school teachers. Following known Learning Management Systems, the developed methodology was successfully formulated and adapted for education.

In this thesis various subjects at the crossroads of quantummechanics and device physics are treated, spanning from afundamental study on quantum measurements to fabricationtechniques of controlling gates for nanoelectroniccomponents. Electron waveguide components, i.e. electronic componentswith a size such that the wave nature of the electron dominatesthe device characteristics, are treated both experimentally andtheoretically. On the experimental side, evidence of partialballistic transport at room-temperature has been found anddevices controlled by in-plane Pt/GaAs gates have beenfabricated exhibiting an order of magnitude improvedgate-efficiency as compared to an earlier gate-technology. Onthe theoretical side, a novel numerical method forself-consistent simulations of electron waveguide devices hasbeen developed. The method is unique as it incorporates anenergy resolved charge density calculation allowing for e.g.calculations of electron waveguide devices to which a finitebias is applied. The method has then been used in discussionson the influence of space-charge on gate-control of electronwaveguide Y-branch switches. Electron waveguides were also used in a proposal for a novelscheme of carrierinjection in low-dimensional semiconductorlasers, a scheme which altogether by- passes the problem ofslow carrier relaxation in suchstructures. By studying aquantum mechanical two-level system serving as a model forelectroabsorption modulators, the ultimate limits of possiblemodulation rates of such modulators have been assessed andfound to largely be determined by the adiabatic response of thesystem. The possibility of using a microwave field to controlRabi oscillations in two-level systems such that a large numberof states can be engineered has also been explored. A more fundamental study on quantum mechanical measurementshas been done, in which the transition from a classical to aquantum "interaction free" measurement was studied, making aconnection with quantum non-demolition measurements.

The aim of this thesis in the nanoelectronics domain is to present a contribution to the analysis of the quantum electronic transport phenomena in nanostructures. For this purpose, we specifically develop the phase field matching theory (PFMT). Within this algebraic approach the electronic properties of the system are described by the tight-binding formalism, whereas the analysis of the transport properties based on the phase matching of the electronic states of the leads to the states of the molecular nanojunctions. By comparing some of our results with those of the first principles methods, we have shown the correctness and fonctionality of our approach. Moreover, our method can be considered as a practical and general alternative to the Green's function-based techniques, and is applied in this work to model the electronic transport across mono and diatomic nanojunctions, consisting of mono and multivalent Na, Cu, Co, C, Si, Ga and As elements.

Fabrication of nanoscale Josephson junctions and Superconducting Quantum Interference Devices (SQUID) is very promising but challenging topic in the superconducting electronics and device technology. In order to achieve best sensitivity of SQUIDs and to reproduce them easily with a straightforward method, new fabrication techniques for realization of nanoSQUIDs needs to be investigated. This study concentrates on investigation of new fabrication methodology for manufacturing nanoSQUIDs with High Temperature Bi-Crystal Grain Boundary Josephson Junctions fabricated onto SrTiO3 bi-crystal substrates using YBa2Cu3O7-δ (YBCO) thin-films. In this process nanoscale patterning of YBCO was realized by using electron beam patterning and physical dry etching of YBCO thin films on STO substrates. YBCO thin films were deposited using RF magnetron sputtering technique in the mixture of Ar and O2 gases and followed by annealing at high temperatures in O2 atmosphere. Structural characterization of YBCO thin films was done by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Spectroscopy (EDX). Superconducting properties of thin films was characterized by AC magnetic susceptibility measurements. Nanoscale structures on YBCO thin films were fabricated by one E-Beam Lithography (EBL) step followed by Reactive Ion Etching (RIE) and physical dry etching. First SiO2 thin film were deposited on YBCO by RF magnetron sputtering and it was patterned by EBL using Polystyrene (PS) as resist material and RIE. Then SiO2 was used as an etch mask for physical dry etching of YBCO and nanoscale structures on YBCO were formed.

Motivated by the necessity to consider probabilistic approaches to future designs, the main objective of this thesis was to develop and characterize energy efficient probabilistic CMOS (PCMOS) circuits that can be used to implement low energy computing platforms. The simplest circuit characterized was a PCMOS inverter (switch). An analytical model relating the energy consumption per switching (E) of this switch to its probability of correctness, p was derived. This characterization can also be used to evaluate the energy and performance savings that are achieved by PCMOS switch based computing platforms. The characterization of a PCMOS inverter was also extended to larger circuits whose probabilistic behavior was analyzed by first developing probability models of primitive gates, which were then input to a graph-based model to find the probabilities of larger circuits. The analysis of larger probabilistic circuits provides a basis for analyzing probabilistic behaviors due to noise in future technologies, and can be used in probabilistic design and synthesis methods to improve circuit reliability. Another important design criterion is the speed of a PCMOS circuit. The trade-offs between the energy, speed, and p of PCMOS circuits were also analyzed. Based on this study, various methods were proposed to optimize energy delay product (EDP) and p under given constraints on p, performance, and EDP. The sensitivity of the analysis with respect to variations in temperature, supply voltage, and threshold voltage was also considered.

Graphene grown epitaxially on silicon carbide provides a potential avenue toward industrial-scale graphene electronics. A predominant aspect of the multilayer graphene produced on the carbon-terminated (000 -1) face of SiC is the rotational stacking faults between graphene layers and their associated moire-pattern superlattice. We use scanning tunneling microscopy (STM) and spectroscopy (STS) in high magnetic fields to obtain detailed information about the "massless Dirac fermions" that carry charge in graphene. In agreement with prior investigations, we find that for small magnetic fields, the rotational stacking effectively decouples the electronic properties of the top graphene layer from those below. However, in maps of the wavefunction density at magnetic fields above 5 Tesla, we discover atomic-scale features that were not previously known or predicted. A phenomenological theory shows that this high-field symmetry-breaking is a consequence of small cyclotron-orbit wavefunctions, which are sensitive to the local layer stacking structures internal to the moire superlattice cell. The broken symmetry is sublattice degeneracy, predicated by atomic scale variations that derive from the sublattice polarization of graphene wavefunctions.

<p>In this thesis various subjects at the crossroads of quantummechanics and device physics are treated, spanning from afundamental study on quantum measurements to fabricationtechniques of controlling gates for nanoelectroniccomponents.</p><p>Electron waveguide components, i.e. electronic componentswith a size such that the wave nature of the electron dominatesthe device characteristics, are treated both experimentally andtheoretically. On the experimental side, evidence of partialballistic transport at room-temperature has been found anddevices controlled by in-plane Pt/GaAs gates have beenfabricated exhibiting an order of magnitude improvedgate-efficiency as compared to an earlier gate-technology. Onthe theoretical side, a novel numerical method forself-consistent simulations of electron waveguide devices hasbeen developed. The method is unique as it incorporates anenergy resolved charge density calculation allowing for e.g.calculations of electron waveguide devices to which a finitebias is applied. The method has then been used in discussionson the influence of space-charge on gate-control of electronwaveguide Y-branch switches.</p><p>Electron waveguides were also used in a proposal for a novelscheme of carrierinjection in low-dimensional semiconductorlasers, a scheme which altogether by- passes the problem ofslow carrier relaxation in suchstructures. By studying aquantum mechanical two-level system serving as a model forelectroabsorption modulators, the ultimate limits of possiblemodulation rates of such modulators have been assessed andfound to largely be determined by the adiabatic response of thesystem. The possibility of using a microwave field to controlRabi oscillations in two-level systems such that a large numberof states can be engineered has also been explored.</p><p>A more fundamental study on quantum mechanical measurementshas been done, in which the transition from a classical to aquantum "interaction free" measurement was studied, making aconnection with quantum non-demolition measurements.</p>

Increased challenges in CMOS scaling have motivated the development of alternatives to silicon circuit technologies, including graphene transistor development. In this work, we present a circuit simulator model for graphene FETs, developed to both fit measured data and predict new behaviors, motivating future research. The model is implemented in Agilent ADS, a circuit level simulator that is commonly used for non-standard transistor technologies, for use with parameter variation analyses, as well as easy integration with CMOS design kits. We present conclusions drawn from the model, including analyses on the effects of contact resistance and oxide scaling. We have also derived a quantum-capacitance limited model, used to intuit intrinsic behaviors of graphene transistors, as well as outline upper bounds on performance. Additionally, the ideal frequency doubler has been examined and compared with graphene, and performance limits for graphene frequency multipliers are elucidated. Performance as a demodulator is also discussed. We leverage this advancement in modeling research to advance circuit- and system-level research using graphene transistor technology. We first explore the development of a GHz planar carbon antenna for use on an RF frontend. This research is further developed in work towards the first standalone carbon radio on flexible plastics. A front end receiver, comprised of an integrated carbon antenna, transmission lines, and a graphene transistor for demodulation, are all fabricated onto one plastic substrate, to be interfaced with speakers for a full radio demo. This complete system will motivate further research on graphene-on-plastic systems. / text

Nanoscale materials enable unique opportunities at the interface between physical and life sciences. The interface between nanoelectronic devices and biological systems makes possible communication between these two diverse systems at the length scale relevant to biological functions. The development of a bottom-up paradigm allows the nanoelectronic units to be synthesized and patterned on unconventional substrates. In this thesis, I will focus on the development of three-dimensional (3D) nanoelectronics, which mimics the structure of porous biomaterials to explore new methods for seamless integration of electronics with other materials, with a special focus on biological tissue. / Chemistry and Chemical Biology

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