Pierre Franck

Mesoscopic Model for the Electromagnetic Properties of Arrays of Nanotubes and Nanowires: A Bulk Equivalent Approach

We propose a new bulk approach to the electromagnetic (EM) modeling of nanotubes (NTs) and nanowires (NWs) in arrays or bundles of arbitrary shape and size. The purpose of this model is to enable feasible and efficient EM analysis of electronics designs incorporating these novel materials by using the available software. A general and straightforward approach to derive anisotropic bulk conductivity from single-element models is exposed. The specific model for single-wall carbon nanotubes (SWCNTs) is then adapted from a broadly accepted one. Both models have been implemented in two different 3D EM solvers. Through simulation of single and bundled carbon nanotube (CNT) structures, we demonstrate the near equivalence of both models in transmission as well as in radiation. Finally we demonstrate, for the first time, the full EM simulation of a device integrating CNTs.

Carbon Nanostructures Dedicated to Millimeter-Wave to THz Interconnects

This paper focuses on the use of CNTs for new mm-to-THz interconnects for nanopackaging. To successfully integrate CNT to be in line with nanoelectronics trends, new growth processes and modeling approaches are proposed. Several experimental works are presented such as millimeter-wave flip-chip bonding. In addition, novel THz 3-D wireless interconnect, based on CNT monopole antennas, working at 200 and 300 GHz are designed, simulated, and fabricated.

Trade-offs in designing antennas from bundled carbon nanotubes

As a preliminary step towards the design of carbon-nanotube-based nano-antennas, we investigate the resonant behavior of bundled carbon nanotubes in a monopole configuration. Simulation is performed using a 3D EM method to ensure comprehensive coverage of the various effects in the bundle. The necessary trade-offs between size reduction, impedance matching, and operating frequency are highlighted.

Plasmon resonances of carbon-nanotube-based dipole antennas for nano-interconnects

We investigate the use of bundled carbon nanotubes (CNTs) as nano-antennas for chip-to-chip and on-chip communications. We model CNTs as hollow tubes with complex surface conductivity. This is implemented in two finite-elements-method 3D electromagnetic solvers. Single-CNT-arms dipoles are simulated to validate our modeling approach by comparing our results to those found in literature. We then extend the study to bundles of CNTs. Finally we simulate the transmission between two CNT dipoles.

Monopole antenna based on carbon nanotubes

A millimeter-wave monopole antenna model is presented in this paper. A size reduction of the quarter-wavelength antenna is demonstrated using the carbon nanotube quantum effects and more precisely its kinetic inductance to low down the propagation velocity through the tube. This 3-D approach offers a high potential of compactness for the increase of frequency at the W-band and above. A comparison of performance with existing monopole antenna made by gold will be done.

Performance assessment of optimized carbon-nanotube-based wireless on-chip communication

We use 3D FEM simulation to study electrically-short carbon-nanotube-based antennas and their application to wireless on-chip communication. We first expose our model for single-wall carbon nanotubes and our simulation technique. This is then used to study extensively the various parameters involved in the design of a planar dipole antenna made of carbon nanotubes aligned over a quartz substrate. From this study, an appropriate design is selected and studied in an antenna-to-antenna transmission link.

Carbon-nanotube-based electrically-short resonant antennas

We present a study on using carbon nanotubes (CNTs) as the radiating part of resonant antennas in order to reduce their dimensions. A mesoscopic electromagnetic (EM) model for CNTs was developed to allow the simulation of RF devices in classical EM solvers while retaining the specific properties of CNTs. A circuit approach is also used to provide a physical interpretation of the results on monopole antennas and trend prediction. These techniques constitute a platform to study the trends and trade-offs involved in the design of these antennas. Finally, these results are used to assess suitable fabrication techniques for CNT-based short resonant antennas and conclusions are drawn on their potential applications.

Design and assessment of carbon-nanotube-based remote links to nanodevices

We use 3D FEM simulation to study realistic designs of electrically-short carbon-nanotube-based antennas and their application to wireless on-chip communication. We first expose the simulation technique we use. We then describe a feasible planar dipole antenna made of carbon nanotubes aligned over a quartz substrate and our preliminary fabrication results. We extensively study the various parameters involved in its design. From this study, an appropriate design is selected and studied in an antenna-to-antenna transmission link.

A bulk equivalent model of carbon-nanotube arrays : Application to the design of novel antennas

We report the efforts lead in the design and fabrication of novel antennas from carbon nanotubes (CNTs) to assess their practicality in diverse usage scenarios. CNT-based antennas could help improve the performance of electrically-small antennas and for instance be used for RF interconnect or to link nano to micro world. They also represent an interesting technology for millimeter-wave and THz applications. Significant progress has been made on each of the four intertwined axes pertaining to these special antennas, modeling, analysis, fabrication and characterization. This has allowed designing and fabricating the first electrically-short CNT antenna prototypes. Indeed, we have derived an original mesoscopic model for the electromagnetic properties of aligned arrays of nano-elements with a special focus on CNTs to match simulation and fabrication capabilities. In parallel, we have reproduced and developed CNT growth and deposition techniques and established scalable fabrication processes. Additionally, an analytical model for CNT-based monopole antennas has been derived from transmission line theory. By combining modeling, analysis, simulation and fabrication, we have finally achieved the design and fabrication of CNT-based monopole antenna prototypes.

Carbon-nanotube-based RF components with multiple applications

Owing to their extraordinary electronic properties, carbon nanotubes (CNTs), as a building block, promise superior performance and novel functionalities for microwave electronic components. This review presents some of the last results obtained in three different fields of this fast moving area - antennas, interconnects and sensors. Electromagnetic and analytical models are used to evaluate and optimize component performance. Synergy between fabrication and simulation techniques allows the practical design of bundled-CNTs-based components. Opportunities are discussed from the fabrication of CNT materials (PECVD, CVD) to their implementation in components and systems by specific technological processes (Photolithography, Flip-Chip, Inkjet printing, etc.). Actual performance of fabricated prototypes and expected improvement based on the CNTs implementation are presented.