The International Journal of Nano Device, Sensor and Systems (IJ-Nano) is an international Journal devoted to nano science and technology of all types of device, sensor and electronic systems. The journal comprises original and significant experimental and theoretical contributions on a wide array of topics relating (but not limited) to the following: the theory, design, modelling, simulation, fabrication and characterization of micro- and nanometer devices for electronics, advanced solid state devices concept and properties, emerging nanodevices (e.g. carbon nanotubes, graphene, single electron transistors, spintronics), transport mechanism in electronic materials, thin/thick film materials, nanomaterials for device fabrication, compound semiconductors, optoelectronics, photovoltaic, organic and molecular electronics, semiconductor-based sensors and actuators,micro- & nanofluidics, electro mechanical systems (MEMS/NEMS), system on chip, nanocircuit and nanosystem, analogue and digital circuit design, VLSI technology, FPGA-based system design and evaluation, thermal/power analysis of integrated circuit and embedded systems and reliability issues of electronic devices. The wide scope of the Journal encompasses Low power VLSI system systems, wireless communications and signal processing, portable communications and multimedia devices and architectures for low power devices and components.
In recent past extensive simulation work on Tunnel Field Effect Transistors (TFETs) has already been done. However this is limited to device performance analysis. Evaluation of circuit performance is a topic that is very little touched. This is due to the non-availability of compact models of TFETs in the commercial simulator. We generate the TFET model by using the model editor in Cadence OrCAD V16.0. In this paper for the first time we perform the circuit analysis of Extended Channel Tunnel Field Effect Transistors (Extended Channel TFETs), we test them over basic digital circuit. Before that we perform device analysis of double gate extended channel TFETs, extended channel has been tried before on SOI TFETs, we try it for the first time on double gate Si1-xGex TFETs. We even look at the effect of introducing Si layer. The performance of this device is compared for different Ge mole fraction and also with MOSFETs.
The carrier propagation in quasi two dimensional strained silicon is quantum confined in the direction normal to the channel; while has the analog energy spectrum in the other two Cartesian direction. In this paper, we report the Einstein relation that relates the diffusivity to the carrier mobility of two dimensional strained silicon for both the nondegenerate regime and degenerate regime. The germanium fraction, x in the relaxed Si1-xGex is taken to be 20%. The Fermi Dirac distribution function in the form of Fermi integral order zero, is employed in developing the carrier statistic and the intrinsic velocity. It was demonstrated that the Einstein Relation is related to the channel width in nondegenerate regime but in degenerate regime, it is related to the channel width, carrier concentration and the effective density of state. Also, the intrinsic velocity shows the carrier concentration dependence behavior in the degenerate regime but is dependence of the temperature in the nondegenerate regime.
RTD sensor resistances and temperature coefficients are relatively small. Lead wires with a total resistance as low as 10 Ω and relatively high temperature coefficients can change the data acquisition system’s calibration. The lead wire’s resistance change over temperature can add to or subtract from the RTD sensor’s output and produce appreciable errors in temperature measurement. Three-wire RTD measurement technique using a current source is widely used in industries for the measurement of RTD résistance. The benefit of 3 wire RTD connection over the 4 wire RTD is one less lead wire. However, this connection assumes that the two current-carrying wires have the same resistance. Novel approach for the measurement of RTD resistance through 3-wire cancellation using software techniques with constant voltage source (instead of current source) is proposed and implemented successfully.
Two main concepts in design and construction of stress and fine motion detection system using fiber optic sensor was included in this project. The first is design and construction concept using Intensity Modulation techniques using plastic multimode optical fiber (125μm dim) and has NA=0.27 with losses rate 2.1 db and directionality about 25 db, and we used He-Ne laser source (632.8 nm) with LLM-2 light power meter to detect the variation in output laser power due to micro-displacement for movement body under test. The second concept includes Modeling for laser beam tracking through fiber and that which reflected for mirror to detector. Variation in output power due to target movement was theoretical analyzed from study of variation of Gaussian front wave profile of using MATLAB program within displacement range from 0-5 mm. Non-linear relation between separated distance and beam intensity was investigated. Finally our design are evaluated in comparison with published research which is found compatible in theoretical and experimental results.
Safety as a main parameter on the industry activates leads to work on the smoke detection sensors. In this paper, fabrication steps of a gas sensor based on the Sol-Gel method and also the industrial application of the fabricated sensor for smoke detection is investigated. A system called\\\\\\\" Spinner\\\\\\\" at temperature 4000C is employed to fabricate a thinner sensitive sensor. To produce a thin layer of \\\\\\\"Tin Oxide\\\\\\\", lean Decoloured (sncl2) is deposited, and glass is used as the base substrate. A process called \\\\\\\" spin Coating \\\\\\\" several times are tried on the \\\\\\\" Spinner \\\\\\\" to find an optimal speed of fabrication. The thickness of layers depends on the speed of spinner thus different thicknesses of layers according to different types of the spinner speed can be fabricated. In this research the electrical resistance and sensitivity graphs according to the spinner speed is presented in the response of different temperatures for CO2 gas. Our research after analyzing the obtained data and comparing them together indicate that, the suitable sensitivity of the samples can be achieved by the Sol-Gel technique. Also EDX graph (chart), indicates that this method compared to the other methods such as the electrochemical method, performs higher level of purity. In addition based on the fabrication analyze an optimal speed of the spinner around (1500 rpm) is reported.
A semi-empirical analytical model of Si/SixGe1-x, GaAs/AlxGa1-xAs and GaN/AlxGa1-xN resonant tunneling diode (RTD) is presented in this paper. Transmission coefficient (Tc) is an important factor for determining the performance of a resonant tunneling diode. Variation of transmission coefficient with electron energy and other device parameters are predicted with the help of this model. Comparison of performance characteristics of these three devices are made for different barrier width and well width in presence and absence of applied electric field using transfer matrix method.
Nanopositioning, Precise control and manipulation of devices and materials at nanoscale is the most important constraint of nanotechnology. Nanopositioning stage consisting of piezoelectric actuator has widespread use in applications requiring positioning with precision at nanoscale. In this paper, open loop characteristics of the non minimum phase nanopositioning system are investigated. To guarantee high precision positioning and improvement in the system characteristics demands different types of feedback controllers. The main aim of the controller is to design a closed loop system with good dynamic characteristics and to maintain the desired stability margins. PID controller is a generic closed loop controller widely used for industrial control applications. This paper presents design of PID controller using Ziegler Nichols tuning method. This paper analyzes time and frequency response of traditional PID controller. Non minimum phase system can be stabilized more effectively by modern controller such as pole placement controller, Linear Quadratic Regulator (LQR) and H infinity controllers. This paper develops a methodology for the design of full state feedback controller using pole placement and LQR control techniques. Step response and frequency responses under variety of conditions are plotted and analyzed to verify the effectiveness of the proposed controllers. Closed loop system is analyzed in both time and frequency domain for different dynamic characteristics such as rise time, settling time, maximum overshot and stability margins. A comparative assessment based upon the system’s response characteristics of traditional PID controller, pole placement controller and LQR controller is presented. Simulation results for the performance analysis are carried out on MATLAB and demonstrate effectiveness and adaptability of controller for precise control of piezoelectric actuated nanopositioning system.
In this paper, we present a detailed algorithm to compute the current-voltage characteristics of the single electron circuits by Monte Carlo method. Our simulator is designed to solve capacitance systems that contain tunnel junctions. The simulation process is based on orthodox theory. Single electron box, single electron transistor, electron pump and inverter circuits have been investigated, and the results are compared with the previous relevant literature
Carbon Nanotubes are providing a fascinating area of research now a days because of their unique properties like high tensile strength, stiffness, elasticity and biodegradability. The field of nanotechnology and nanoscience push their investigation forward to produce CNTs with suitable parameters for future applications. It is evident that new approaches of their synthesis need to be developed and optimized. CNTs can be synthesized by various methods like arc deposition, laser ablation, chemical vapour deposition, electrochemical synthesis, flame synthesis etc. In this work, pure and high yield CNTs are synthesizedÂ by Â some rarely used way of arc discharge deposition which involves arc discharge in distilled water in contrary to standard used deposition in a gas atmosphere. In addition, I have purified the CNTs and then characterized them by X-ray Diffraction techniques, FTIR and Raman Spectroscopy.
Application of symmetric double gate vertical metal oxide semiconductorfield effect transistors (MOSFETs) is hindered by the parasitic overlapcapacitance associated with their layout, which is considerably larger than fora lateral MOSFET on the same technology node. A simple processsimulation has been developed to reduce the parasitic overlap capacitance inthe double gate vertical MOSFETs by using SOI (Silicon on Insulator) inbottom planar surfaces side. The result shows that while channel lengthdecreases, the threshold voltage goes lower, the DIBL rises and subthresholdswing tends to decrease, for both structures. It is noted that the SOI DGVMOSFET structure generally have better performance in SCE controlcompared to bulk vertical MOSFET. The presence of buried oxide is believed to increase the performance of vertical MOSFET, essentially incontrolling the depletion in subthreshold voltage