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For decades, the revolution in design and fabrication methodology of flexible capacitive pressure sensors using various inorganic/organic materials has significantly enhanced the field of flexible and wearable electronics with a wide range of applications in aerospace, automobiles, marine environment, robotics, healthcare, and consumer/portable electronics. Mathematical modelling, finite element simulations, and unique fabrication strategies are utilized to fabricate diverse shapes of diaphragms, shells, and cantilevers which function in normal, touch, or double touch modes, operation principles inspired from microelectromechanical systems (MEMS) based capacitive pressure sensing techniques. The capacitive pressure sensing technique detects changes in capacitance due to the deformation/deflection of a pressure sensitive mechanical element that alters the separation gap of the capacitor. Due to advancement in state‐of‐the‐art fabrication technologies, the performance and properties of capacitive pressure sensors are enhanced. In this review paper, recent progress in flexible capacitive pressure sensing techniques in terms of design, materials, and fabrication strategies is reported. The mechanics and fabrication steps of paper‐based low‐cost MEMS/flexible devices are also broadly reported. Lastly, the applications of flexible capacitive pressure sensors, challenges, and future perspectives are discussed. [ABSTRACT FROM AUTHOR]

Body integrated wearable electronics can be used for advanced health monitoring, security, and wellness. Due to the complex, asymmetric surface of human body and atypical motion such as stretching in elbow, finger joints, wrist, knee, ankle, etc. electronics integrated to body need to be physically flexible, conforming, and stretchable. In that context, state-of-the-art electronics are unusable due to their bulky, rigid, and brittle framework. Therefore, it is critical to develop stretchable electronics which can physically stretch to absorb the strain associated with body movements. While research in stretchable electronics has started to gain momentum, a stretchable antenna which can perform far-field communications and can operate at constant frequency, such that physical shape modulation will not compromise its functionality, is yet to be realized. Here, a stretchable antenna is shown, using a low-cost metal (copper) on flexible polymeric platform, which functions at constant frequency of 2.45 GHz, for far-field applications. While mounted on a stretchable fabric worn by a human subject, the fabricated antenna communicated at a distance of 80 m with 1.25 mW transmitted power. This work shows an integration strategy from compact antenna design to its practical experimentation for enhanced data communication capability in future generation wearable electronics. [ABSTRACT FROM AUTHOR]

High performance flexible electronics promise innovative future technology for various interactive applications for the pursuit of low-cost, light-weight, and multi-functional devices. Thus, here we show a complementary metal oxide semiconductor (CMOS) compatible fabrication of flexible metal-oxide-semiconductor capacitors (MOSCAPs) with high-κ/metal gate stack, using a physical vapor deposition (PVD) cost-effective technique to obtain a high-quality Ge channel. We report outstanding bending radius ∼1.25 mm and semi-transparency of 30%. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We explore the effectiveness of tin (Sn), by alloying it with silicon, to use SiSn as a channel material to extend the performance of silicon based complementary metal oxide semiconductors. Our density functional theory based simulation shows that incorporation of tin reduces the band gap of Si(Sn). We fabricated our device with SiSn channel material using a low cost and scalable thermal diffusion process of tin into silicon. Our high-κ/metal gate based multi-gate-field-effect-transistors using SiSn as channel material show performance enhancement, which is in accordance with the theoretical analysis. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We demonstrate a new thin film transistor (TFT) architecture that allows expansion of the device width using continuous fin features - termed as wavy channel (WC) architecture. This architecture allows expansion of transistor width in a direction perpendicular to the substrate, thus not consuming extra chip area, achieving area efficiency. The devices have shown for a 13% increase in the device width resulting in a maximum 2.5× increase in 'ON' current value of the WCTFT, when compared to planar devices consuming the same chip area, while using atomic layer deposition based zinc oxide (ZnO) as the channel material. The WCTFT devices also maintain similar 'OFF' current value, ∼100 pA, when compared to planar devices, thus not compromising on power consumption for performance which usually happens with larger width devices. This work offers an interesting opportunity to use WCTFTs as backplane circuitry for large-area high-resolution display applications. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We report the inherent increase in capacitance per unit planar area of state-of-the art high- κ integrated metal/insulator/metal capacitors (MIMCAPs) fabricated on flexible silicon fabric with release-first process. We methodically study and show that our approach to transform bulk silicon (100) into a flexible fabric adds an inherent advantage of enabling higher integration density dynamic random access memory (DRAM) on the same chip area. Our approach is to release an ultra-thin silicon (100) fabric (25 µm thick) from the bulk silicon wafer, then build MIMCAPs using sputtered aluminium electrodes and successive atomic layer depositions (ALD) without break-ing the vacuum of a high- κ aluminium oxide sandwiched between two tantalum nitride layers. This result shows that we can obtain flexible electronics on silicon without sacrificing the high density integration aspects and also utilize the non-planar geometry associated with fabrication process to obtain a higher integration density compared to bulk silicon integration due to an increased normalized capacitance per unit planar area. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We demonstrate a simple, low-cost, and scalable process for obtaining uniform, smooth surfaced, high quality mono-crystalline germanium (100) thin films on silicon (100). The germanium thin films were deposited on a silicon substrate using plasma-assisted sputtering based physical vapor deposition. They were crystallized by annealing at various temperatures ranging from 700 °C to 1100 °C. We report that the best quality germanium thin films are obtained above the melting point of germanium (937 °C), thus offering a method for in-situ Czochralski process. We show well-behaved high- κ /metal gate metal-oxide-semiconductor capacitors (MOSCAPs) using this film. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

In the 1990s the Message Passing Interface Forum defined MPI bindings for Fortran, C, and C++. With the success of MPI these relatively conservative languages have continued to dominate in the parallel computing community. There are compelling arguments in favour of more modern languages like Java. These include portability, better runtime error checking, modularity, and multi-threading. But these arguments have not converted many HPC programmers, perhaps due to the scarcity of full-scale scientific Java codes, and the lack of evidence for performance competitive with C or Fortran. This paper tries to redress this situation by porting two scientific applications to Java. Both of these applications are parallelized using our thread-safe Java messaging system—MPJ Express. The first application is the Gadget-2 code, which is a massively parallel structure formation code for cosmological simulations. The second application uses the finite-domain time-difference method for simulations in the area of computational electromagnetics. We evaluate and compare the performance of the Java and C versions of these two scientific applications, and demonstrate that the Java codes can achieve performance comparable with legacy applications written in conventional HPC languages. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Adults and immatures of Aedes mosquito populations were collected at temperatures between 40 and 44°C (summer), while larvae were collected at 0°C (winter). Major mosquito activities were observed from February to mid-December at various collection sites that yielded high populations of Aedes spp. from May to September, and high populations of Culex spp. and Anopheles spp. from March to September. In June to July, mosquito activity was suspended because the relative humidity was high (70%); a result of the monsoon rains. In August, with temperature ranging from 38 to 42°C, the populations of Culex, Anopheles and Aedes began to increase (36.8, 32.1 and 26.3%, respectively). Population estimates (through standard prototype Centers for Disease Control (CDC) and Biogents (BG)-sentinel) and species composition of Aedes in forest habitats indicated a rapid increase in the populations of Ae. albopictus (52.3%), Ae. aegypti (19.1%) and Ae. vittatus (28.5%) following the rainy season in July. Areas positive for Ae. albopictus had identical population levels and distribution ranges of Ae. vittatus, however, there were no Ae. aegypti in Ae. albopictus areas from August to September. The population level, seasonal distribution, habitat and areas of adult activity marked by global positioning system (GPS) coordinates are being used for reference and for species composition data of Anopheles spp. (2), Culex spp. (10) and Aedes spp. (5) in addition to associated temperature, relative humidity and physico-chemical factors of larval habitat. Global meteorological changes have caused an expansion of the active period, leading to the mosquito's possibility of being a vector of disease increasing, resulting in the spread of dengue fever. [ABSTRACT FROM AUTHOR]

Applications of flexible capacitive pressure sensors, capacitive sensing, flexible capacitive pressure sensors, flexible sensors, pressure sensing Flexible Capacitive Pressure Sensors: Recent Progress on Flexible Capacitive Pressure Sensors: From Design and Materials to Applications (Adv. Keywords: applications of flexible capacitive pressure sensors; capacitive sensing; flexible capacitive pressure sensors; flexible sensors; pressure sensing EN applications of flexible capacitive pressure sensors capacitive sensing flexible capacitive pressure sensors flexible sensors pressure sensing 1 1 1 04/07/21 20210401 NES 210401 In article number 2001023, Muhammad M. Hussain and co-workers provide a comprehensive review on flexible capacitive-based pressure sensors with a focus on their design approaches and state-of-the-art fabrication techniques. [Extracted from the article]

The design and fabrication of a rolled dielectric elastomer actuator is described and the parametric dependence of the displacement and blocked force on the actuator geometry, elastomer layer thickness, voltage, and number of turns is analyzed. Combinations of different elastomers and carbon nanotube electrodes are investigated and optimized to meet performance characteristics appropriate to tactile display applications, namely operation up to 200 Hz with a combination of a 1 N blocked force and free displacement of 1 mm, all within a volume of less than 1 cm3. Lives in excess of 50 000 cycles have been obtained. Key to meeting these objectives is control of the multilayering fabrication process, the carbon nanotube electrode concentration, the selection of a soft elastomer with low viscous losses, and a proof‐testing procedure for enhancing life cycle reliability. A flexible manufacturing approach based on multilayering elastomers and carbon nanotube electrodes followed by rolling is proposed. Combinations of different elastomers, carbon nanotube electrodes, and geometries are investigated analytically and experimentally and optimized to meet performance characteristics appropriate to tactile display applications in both static mode and dynamic mode. [ABSTRACT FROM AUTHOR]

Body‐integrated wearable electronics for health monitoring, security, and wellness applications required flexible, conforming, and stretchable electronics, due to the motion of the human body. On page 6565, J. A. Rogers, A. Shamim, M. M. Hussain and co‐workers develop a helical spring‐based flexible and out‐of‐plane‐stretchable antenna made with copper and showing constant frequency operation for far field communication—demonstrating a major advancement in wearable and implantable electronics. [ABSTRACT FROM AUTHOR]

A low‐cost simple thin film deposition of tin (Sn), followed by thermal annealing based alloying of it into the silicon channel, leads to an enhancement of the performance of silicon‐based CMOS devices. Modelling based on density functional theory (DFT) shows that Sn incorporation may lower the band gap of the silicon channel, while the experimental multi‐gate field effect transistor devices show performance enhancement. Additionally, the device performance analysis indicates its promising usage in low standby power applications for ultra‐mobile computation. The study by Aftab M. Hussain et al. (pp. 332–335) opens up further exploration opportunity for group IV(a) (in the periodic table) based materials for channel engineering in semiconductor device technology. [ABSTRACT FROM AUTHOR]

As shown by Hanna et al. (pp. 248–251), by gENerating a wavy architecture in classical transistor topology, high output currENt is achieved – opENing up bold futuristic opportunity for ultra ‐ high resolution bright display. Irrespective of the material choice – the unique architecture can provide exciting thin film transistor performance ENhancemENt.Hanna et al. demonstrate the advantage of using the wavy architecture in terms of area efficiENcy, higher output currENt, higher field ‐ effect mobility and similar OFF currENt levels and Ion/Ioff ratios compared to the planar counterparts for a thin film transistor fabricated with zinc oxide channel material. The low OFF currENt levels and high Ion/Ioff ratios for the wavy ‐ channel devices ENsure that standby power consumption remains similar to the planar counterparts, while improving the ON currENt values. This proves the significance of this new architecture for large ‐ area high ‐ resolution display applications. [ABSTRACT FROM AUTHOR]