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In the present work, a new concept of x-ray source was developed. The conventional thermionic tungsten filament tube is commonly available in various fields of application, such as, medical diagnostic and therapy system, microwave amplifier, non-destructive testing (NDT) technology, and so on. However, it has intrinsic problems such as high power consumption, very low x-ray efficiency, and out-gassing problems. Therefore, in the present study a new carbon nanotube (CNT) based x-ray source was developed as a substitute for the conventional one. The new x-ray source consists of three major parts. The CNT electron field emitter was employed as a cathode, a very thin metal mesh as a grid to extract electrons from the CNT, and finally a molybdenum embedded copper target as an anode to accelerate electrons. A supplementary electrostatic focusing lens was employed in the tube to focus the electron beam on the anode target. A detailed description of the tube structure as well as electron beam characteristics is presented in this study. In addition, preliminary x-ray images obtained by using the CNT x-ray tube are presented. Index Terms--Carbon nanotube (CNT), field emission, high resolution imaging, inspection system, X-ray source.

Comprehensive modeling and design methods for carbon nanotube (CNT)-based interconnects are developed, which are used for examining the performance, reliability and fabrication requirements for future nanotube-based interconnect solutions. The large diameter MWCNT bundles are more susceptible to process variations than SWCNT bundles, which have important implications for their utilization in future nanoscale integrated circuits.

This paper presents a comparative analysis of the electromagnetic properties of new composite materials that are of interest to future aircraft/aerospace structures. The fabrication process of single-phase and new multiphase micro/nanocomposites is described. Carbon black, carbon fibers, and multiwall carbon nanotubes are randomly mixed into an epoxy resin matrix at various weight fractions and compositions. The experimental characterization in the frequency range 8-18 GHz shows that the dispersion characteristics of short-carbon-fiber-reinforced composites can be properly controlled by the addition of nanopowders and nanotubes into the mixture. Numerical simulations demonstrate the feasibility of the fabricated materials for the design of new electromagnetic micro/nanostructured shields and radar-absorbing laminates. Thin dielectric Salisbury screens are especially designed to exhibit minimum reflection coefficient at 15 GHz. It shows that the total thickness of the screen can be reduced below 2 mm by using a lossy sheet made of three-phase composites. Index Terms--Advanced composite materials, aircraft, multiwall carbon nanotubes, radar-absorbing materials, shielding.

We report for the first time to our knowledge large-signal measurements performed at 600 MHz and in time domain on carbon nanotube field-effect transistors (CNFETs) using a large-signal network analyzer. To overcome the very high mismatch between the high CNFET impedance and the basic 50-[ohm] configuration of the setup, the output impedance was matched with the help of an experimental active load-pull configuration. Hence, we were able to observe under large-signal conditions the nonlinear behavior of CNFETs. Static measurements and continuous-wave S/j-parameter measurements were made for many different biases. They were used in order to determine a nonlinear electrical model that has been validated thanks to the nonlinear measurements. The developed model opens the way for electrical CNFET circuit simulation and nonlinear applications of these devices. Index Terms--Carbon nanotube field-effect transistor (CNFET), large-signal network analyzer (LSNA), neuronal modeler, non-linear model.

The fabrication and functional characterization of a thin-film bulk-acoustic resonator (TFBAR) gas sensor onto a silicon substrate are discussed. A nanocomposite layer of carbon nanotubes, prepared by the Langmuir-Blodgett technique has been shown to be used for the functionalization of the sensor.

The improvement of the interpixel uniformity by individually controlling the luminance of all subpixels in a display panel is discussed. The correction method has ensured the improvement of the interpixel uniformity in large-size carbon nanotube field emission display (CNT-FED).

Scaling of Silicon transistors continue ill the sub 100-nm regime amidst severe roadblocks. Increased short-channel effects, rising leakage currents, severe process parameter variations are only a few of the overwhelming challenges that the device and circuit designers are laced with. In an attempt to alleviate the problems associated with the scaling of silicon transistors, researchers have began a quest for novel alternate materials in a post-Si nanoelectronics era. Of the different materials investigated so far, carbon nanotubes with their superior transport properties, excellent thermal conductivities and high current handling capacities have proved to be a potential heir to St. This paper reviews the promise of carbon nanotube field-effect transistors as future devices for high-performance as well as low-power electronics. Index Terms--Carbon nanotubes, high-speed logic, low-power circuits, subthreshold logic.