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Smart biosensors that can perform sensitive and selective monitoring of target analytes are tremendously valuable for trinitrotoluene (TNT) explosive detection. In this research, the pre-developed sensor was integrated with biological receptors in which they enhanced the sensitivity of the sensor. This is due to conjugated polydiacetylene onto a peptide-based molecular recognition element (Trp-His-Trp) for TNT molecules in graphene field-effect transistors (GR-FETs) as biosensor that is capable of responding to the presence of a TNT target with a colorimetric response. The authors confirmed the efficacy of the receptor while being attached to polydiacetylene (PDA) by observing the binding ability between the Trp-His-Trp and TNT to alter the electronic band structure of the PDA conjugated backbones. The purpose of this paper is to demonstrate a modular system capable of transducing small-molecule TNT binding into a detectable signal. The details of the real-time and selective TNT biosensor have been reported.

Following an introduction, this paper describes the way of fabrication GR-FETs with conventional photolithography techniques and the other processes, which is functionalized by the TNT peptide receptors. The authors first determined the essential TNT recognition elements from UV-visible spectrophotometry spectroscopy for PDA sensor unit fabrication. In particular, the blue percentage and the chromic response were used to characterize the polymerization parameter of the conjugated p backbone. A continuous-flow trace vapor source of nitroaromatics (two, four, six-TNT) was designed and evaluated in terms of temperature dependence. The TNT concentration was measured by liquid/gas extraction in acetonitrile using bubbling sequence. The sensor test is performed using a four-point probe and semiconductor analyzer. Finally, brief conclusions are drawn.

Because of their unique optical and stimuli-response properties, the polydiacetylene and peptide-based platforms have been explored as an alternative to complex mechanical and electrical sensing systems. Therefore, the authors have used GR-FETs with biological receptor-PDAs as a biosensor for achieving high sensitivity and selectivity that can detect explosive substances such as TNT. The transport property changed compared to that of the field-effect transistors made by intrinsic graphene, that is, the Dirac point position moved from positive Vg to negative Vg, indicating the transition of graphene from p-type to n-type after annealing in TNT, and when the device was tested from RT, the response of the device was found to increase linearly with increasing concentrations. Average shifting rate of the Dirac peak was obtained as 0.1-0.3 V/ppm. The resulting sensors exhibited at the limit ppm sensitivity toward TNT in real-time, with excellent selectivity over various similar aromatic compounds. The biological receptor coating may be useful for the development of sensitive and selective micro and nanoelectronic sensor devices for various other target analytes.

The detection of illegally transported explosives has become important as the global rise in terrorism subsequent to the events of September 11, 2001, and is at the forefront of current analytical problems. It is essential that a detection method has the selectivity to distinguish among compounds in a mixture of explosives. So, the authors are reporting a potential solution with the designing and manufacturing of electrochemical biosensor using polydiacetylene conjugated with peptide receptors coated on GR-FETs with the colorimetric response for real-time detection of TNT explosives specifically.

The purpose of this paper is to present a DNA hybridization detection sensor. An inexpensive fabrication procedure was used so that the sensors can be disposed economically after the measurement is completed.

Field effect transistor (FET) devices are used in the proposed structure. The FET device acts as a charge detection element and produces an amplified output current based on surface charge variations. As amplification is performed directly at the sensor frontend, noise sources have less effect on the detected signal, and thus, acceptably low DNA concentrations can be detected with simple external electronics. ZnO nano layers are used as the FET active semiconductor channel. Furthermore, a photobiasing approach is used to adjust the operating point of the proposed FET without the need for an additional gate terminal.

The proposed sensor is evaluated by applying matched and unmatched target DNA fragments on the fabricated sensors with capture probes assembled either directly on the ZnO surface or on a nano-platinum linker layer. It is observed that the presented approach can successfully detect DNA hybridization at the nano mole range with no need for complex laboratory measurement devices.

The presented photobiasing approach is effective in the adjustment of the sensor sensitivity and decreases the fabrication complexity of the achieved sensor compared with previous works.

An simple model for the simulation of the electrical behaviour of several types of junction controlled field‐effect transistors is proposed. It is based on the calculation of the carrier concentration in the channel by means of a self‐consistent solution of Schrödinger and Poisson's equation in the direction perpendicular to the current flow. Based on the carrier concentration the dc, the small‐signal, and also the noise properties of the devices may be simulated. The calculated characteristics of a sub‐quarter micron gate GaAs MESFET, a δ‐doped GaAs FET and a Velocity Modulation Transistor will be presented and discussed.

The purpose of this paper is to present computer‐aided simultaneous signal and noise modeling and analysis for mm‐wave field‐effect transistors (FETs) based on scattering parameters approach.

A mm‐wave FET is modeled as three active‐coupled transmission lines, and the developed wave approach is applied to this model to calculate both signal and noise performances of the device.

The measurements show a good match with the calculated data from the point of view of both signal and noise performances of the device.

This CAD‐oriented analysis and modeling can be easily applied to the mm‐wave simulators to improve the simultaneous signal and noise optimization, modeling and analysis of mm‐wave devices, especially for traveling wave transistors in which the distributed model seems to be more exact than the usual lumped models. Also the proposed routine compared to the admittance approach is conceptually more compatible with scattering representations of active and passive circuits. The developed algorithm has been applied successfully to mm‐wave MESFETs and HEMTs.

Reports on the research and development work carried out at Central Research Laboratories Ltd [CRL], concentrating on their physical and chemical sensing techniques and the manufacture of sensors based on silicon field effect transistors [FETs]. Describes the use of FETs in ion sensitive field effect transistors and gives their advantages over conventional ion selective electrodes, suggesting possible application areas might be in clinical blood analysis, soil sampling and water testing. Also looks at the use of FETs in gas sensitive field effect transistors, which have been used in chicken house atmosphere monitoring and for detecting hydrogen induced cracking in oil and gas pipelines. CRL has also been involved in the development of low cost electro‐chemical gas cells by new manufacturing techniques. Concludes with the range of sensor technologies that CRL has expertise in.

Development of (1T-type) ferroelectric random access memory (FeRAM) has most actively progressed since 1995 and motivated by the physical limits and technological drawbacks of the flash memory. 1T-type FeRAM implements ferroelectric layer at the field effect transistor (FET) gate. During the course of the investigation, it was very difficult to form a thermodynamically stable ferroelectric-semiconductor interface at the FET gate, leading to the introduction of one insulating buffer layer between the ferroelectric and the silicon substrate to overcome this problem. In this study, Al₂O₃ a high-k buffer layer deposited by plasma enhanced atomic layer deposition (PEALD) is sandwiched between the ferroelectric layer and silicon substrate.

Ferroelectric/high-k gate stack were fabricated on the silicon substrate and pt electrode. Structural characteristics of the ferroelectric (PZT) and high-k (Al₂O₃) thin film deposited by RF sputtering and PEALD, respectively, were optimized and investigated for different process parameters. Metal/PZT/Metal, Metal/PZT/Silicon, Metal/PZT/Al₂O₃/Silicon structures were fabricated and electrically characterized to obtain the memory window, leakage current, hysteresis, PUND, endurance and breakdown characteristics.

XRD pattern shows the ferroelectric perovskite thin Pb[Zr_0.35Ti_0.65]O₃ film with (101) tetragonal orientation deposited by sputtering and PEALD Al₂O₃ with (312) orientation showing amorphous nature. Multiple angle analysis shows that the refractive index of PZT varies from 2.248 to 2.569, and PEALD Al₂O₃ varies from 1.6560 to 1.6957 with post-deposition annealing temperature. Increase in memory window from 2.3 to 8.4 V for the Metal-Ferroelectric-Silicon (MFS) and Metal-Ferroelectric-Insulator-Semiconductor (MFIS) structure has been observed at the annealing temperature of 500°C. MFIS structure with 10 nm buffer layer shows excellent endurance of 3 × 109 read-write cycles and the breakdown voltage of 33 V.

This paper shows the feature, principle and improvement in the electrical properties of the fabricated gate stack for 1T-type nonvolatile FeFET. The insulating buffer layer sandwiched between ferroelectric and silicon substrate acts as a barrier to ferroelectric–silicon interdiffusion improves the leakage current, memory window, endurance and breakdown voltage. This is perhaps the first time that the combination of sputtered PZT on the PEALD Al₂O₃ layer is being reported.

This paper aims to provide details of recent developments in nanosensors based on graphene.

Following an introduction, this paper first considers some of the motivations for using graphene in sensors. It then describes a selection of recently reported graphene nanosensors for detecting physical variables, gases, chemical species and biological agents. Finally, brief conclusions are drawn.

Graphene exhibits a number of unique properties that make it an intriguing candidate for use in sensors. Research is still at a relatively early stage, but prototype sensors have been demonstrated which respond to numerous physical, molecular and biological variables.

This paper provides a timely review of the use of graphene in sensors.

The purpose of this paper is to present an improved model based on center potential instead of surface potential which is physically more relevant and accurate. Also, additional analytic insights have been provided to make the model independent and robust so that it can be extended to a full range compact model.

The design methodology used is center potential based analytical modeling using Psuedo-2D Poisson equation, with ingeniously developed boundary conditions, which help achieve reasonably accurate results. Also, the depletion width calculation has been suitably remodeled, to account for proper physical insights and accuracy.

The proposed model has considerable accuracy and is able to correctly predict most of the physical phenomena occurring inside the broken gate Tunnel FET structure. Also, a good match has been observed between the modeled data and the simulation results. I_on/I_ambipolar ratio of 10^(−8) has been achieved which is quintessential for low power SOCs.

The modeling approach used is different from the previously used techniques and uses indigenous boundary conditions. Also, the current model developed has been significantly altered, using very simple but intuitive technique instead of complex mathematical approach.

Discusses intelligent materials, intelligent material‐based sensors, their transducing methods, and different kinds of transducers used with smart material‐based sensors. Assumes that the future of intelligent sensors will almost totally depend on intelligent chemistry and intelligent instrumentation. Molecular recognition will widen the horizons of smart systems with the help of VLSI‐based design and fabrication. Discusses different sensor mechanisms, such as ENFETs, immunoFETs, ISFETs and chemFETs and takes a detailed look at potentiometric, amperometric and optical biosensors.

The purpose of this paper is to investigate the application of reliability engineering to oil and gas (O&G) pipeline systems with the aim of identifying means through which reliability engineering can be used to improve pipeline integrity, specifically with regard to man-made incidents (e.g. material/weld/equipment failure, corrosion, incorrect operation and excavation damages).

A literature review was carried out on the application of reliability tools to O&G pipeline systems and four case studies are presented as examples of how reliability engineering can help to improve pipeline integrity. The scope of the paper is narrowed to four stages of the pipeline life cycle; the decommissioning stage is not part of this research. A survey was also carried out using a questionnaire to check the level of application of reliability tools in the O&G industry.

Data from survey and literature show that a reliability-centred approach can be applied and will improve pipeline reliability where applied; however, there are several hindrances to the effective application of reliability tools, the current methods are time based and focus mainly on design against failure rather than design for reliability.

The tools identified do not cover the decommissioning of the pipeline system. Research validation sample size can be broadened to include more pipeline stakeholders/professionals. Pipeline integrity management systems are proprietary information and permission is required from stakeholders to do a detailed practical study.

This paper proposes the minimum applied reliability tools for application during the design, operation and maintenance phases targeted at the O&G industry. Critically, this paper provides a case for an integrated approach to applying reliability and maintenance tools that are required to reduce pipeline failure incidents in the O&G industry.