The objective is to demonstrate a reproducible carbon nanotube (CNT)-based technology for radio frequency (RF) switch working in the range of 40–60 GHz and fulfilling the specifications: low losses, high isolation, and an operating voltage below 30 V. The first processed component had an operating voltage of 14 V for an ohmic contact in a Nano-Electro Mechanical System (NEMS) tweezer design. This result is confirmed by theory with an operating voltage of 13 V. A capacitive-contact NEMS is also developed using multi-walled CNTs (MWCNTs) coated with a SiO2 dielectric layer deposited by electron beam induced deposition method (EBID). High Frequency Simulation Software (HFSS) RF-simulation on an innovative NEMS geometry shows encouraging results with transmission ratios between “on” state and “off” state up to 34% for ohmic-contact switch and 25% for a capacitive-contact switch.

We report investigations on the fabrication and characterization of graphene nanoribbon (GNR) field-effect transistors. Graphene layers are obtained from the thermal decomposition of a Si-face 4H-SiC substrate. To achieve high dynamic performance, a structure with an array of GNR connected in parallel was fabricated by e-beam lithography. The best intrinsic current gain cut-off frequency of 60 GHz and maximum oscillation frequency of 28 GHz were achieved. This study demonstrates the exciting potential of GNR in high-frequency electronics.

In this paper, we investigate the scattering properties of an array of finite-length single-walled carbon nanotubes (SWCNTs), up to terahertz frequencies. The problem is cast in terms of a Pocklington-like equation. The current density along the CNT is described by a quasi-classical transport model, recently proposed. The numerical solution is obtained by means of the Galerkin method. Case studies are carried out, either referred to isolated SWCNTs and an array of SWCNTs, aimed at investigating the frequency behavior of the scattered field.

We present detailed results of the self-consistent analysis of carbon nanotube (CNT) field-effect transistors (FET), previously extended by us to the case of multi-walled/multi-band coherent carrier transport. The contribution to charge transport, due to different walls and sub-bands of a multi-walled CNT, is shown to be generally non-negligible. In order to prove the effectiveness of our simulation tool, we provide interesting examples about current–voltage characteristics of four-walled semi-conducting nanotubes, including details of numerical convergence and contribution of sub-bands to the calculation.

The effective method of carbon nanotubes antennas' parameters calculation has been developed. The frequency dependencies of input impedance of CNT in dielectric medium have been investigated. It is shown that an increase in the length of a nanotube length does not lead to the appearance of resonances in the centimeter wavelength range.

Carbon nanotubes (CNTs) are a unique group of materials with high aspect ratio, mechanical and electrical properties, which are of great interests in the field of interconnects, and radio frequency applications. In order to incorporate CNTs into any of these applications successfully, one important issue that has to be resolved is the critical parameters (temperature and reactant gases) associated with the growth of the CNTs. As such, the effect of these growth requirements on the adjacent components should be studied. In this work, we examined specifically the effect of carbon nanotubes growth on the underlying metallization, in particular gold, dedicated for radio-frequency-based applications. The gold coplanar lines were annealed at 800°C in a plasma-enhanced chemical vapor deposition (PECVD) system to simulate the worst-case condition. The reflection and transmission parameters were analyzed using a probe station connected to a vector network analyzer. Carbon nanotubes grown on different barrier layers were also characterized using a scanning electron microscope and Raman spectroscopy to identify a suitable barrier layer for gold. Our results showed that it is promising to integrate carbon nanotubes grown using PECVD onto Au coplanar waveguide without degrading the S-parameters measurements up to 20 GHz.

In this paper, double-walled carbon nanotubes (DWNTs) network layers were patterned using inkjet transfer printing. The remarkable conductive characteristics of carbon nanotubes (CNTs) are considered as promising candidates for transmission line as well as microelectronic interconnects of an arbitrary pattern. In this work, the DWNTs were prepared by the catalytic chemical vapor deposition process, oxidized and dispersed in ethylene-glycol solution. The DWNTs networks were deposited between electrodes contact and then characterized at DC through current–voltage measurements, low frequency, and high frequency by scattering parameters measurements from 40 MHz up to 40 GHz through a vector network analyzer. By varying the number of inkjet overwrites, the results confirm that the DC resistance of DWNTs networks can be varied according to their number and that furthermore the networks preserve ohmic characteristics up to 100 MHz. The microwave transmission parameters were obtained from the measured S-parameter data. An algorithm is developed to calculate the propagation constant “γ”, attenuation constant “α” in order to show the frequency dependence of the equivalent resistance of DWNTs networks, which decreases with increasing frequency.

A recently developed material based on carbon nanotubes is used here for the realization of single- and double-layered frequency-selective surfaces (FSSs) with relevant absorbing properties. The peculiar characteristics of carbon nanotubes are exploited to devise high-loss resonant ring structures periodically arranged to build the FSS. By introducing two layers of rings, an absorber with stable characteristics over a wide frequency band and over a wide range for the incident wave angle is achieved.

In this paper, we present a microwave absorber based on carbon nanotubes (CNT) dispersed inside a BenzoCycloButen® (BCB) polymer. The high aspect ratio and remarkable conductive characteristics of CNT give rise to good absorbing properties for electromagnetic protecting in microelectronic devices with very low concentration. In this article, nanocomposites are prepared using a solution-mixing method and are then evaluated and modeled by means of coplanar test structures. First, CNT concentrations are quantified by image processing. The nanocomposites implemented with coplanar test waveguides are then characterized using a vector network analyzer from 40 MHz to 20 GHz. An algorithm is developed to calculate the propagation constant “γ”, attenuation constant “α”, and relative effective complex permittivity (ɛreff = ɛreff′ − jɛreff″) for each CNT concentration. The extracted effective parameters are verified using the electromagnetic FEM-based Ansoft's® high frequency structure simulator (HFSS). Power absorption (PA) of 7 dB at 15 GHz is obtained with only 0.37 weight percent of CNT concentration in the polymer matrix. The resulting engineerable and controllable composite provides consequently a novel degree of freedom to design and optimize innovative microwave components.