Graphene nanoelectronics is an emerging area of research. The 2010 Nobel Prize for physics was awarded to A. Geim and K. Novoselov the discovery graphene its unexpected physical properties, paving way many new applications in nanoelectronics, nanooptics, solid state physics. most-studied microwave device transistor, which, only three years, has reached a cutoff frequency 100 GHz. As consequence this impressive development, prediction that 0.5-1 THz FET transistor will soon be demonstrated...

The paper presents the experimental and modeling results of a microwave slot antenna in coplanar configuration based on graphene. antennas are fabricated 4 in. high-resistivity Si wafer, with ∼300 nm SiO2 layer grown through thermal oxidation. A CVD graphene is transferred SiO2. shows that reflection parameter can be tuned by DC voltage. 2D radiation patterns at various frequencies X band (8–12 GHz) then presented using as backside absorbent metalized surface. Although efficiency lower than...

The radio-frequency identification (RFID) concept is expanded to millimeter-wave frequencies and (MMID) in this paper. MMID a comparison with UHF RFID are presented, showing the limitations benefits of MMID. Three feasible applications suggested for MMID, which are: (1) wireless mass memory; (2) an automatic system pointing functionality; (3) transponder communication automotive radar. To demonstrate feasibility system, experimental results both downlink backscattering-based uplink presented...

We report on measurements and modeling of microwave propagation in graphene. In deep contrast with carbon nanotubes, which display very high impedances the range, planar waveguides patterned directly graphene a 50 Ω impedance, is tuned slightly by an applied dc. The values kinetic impedance nanotubes were not observed

In this letter, we demonstrate that a graphene monolayer, over which three metallic electrodes forming coplanar waveguide are patterned, acts as frequency multiplier and generates frequencies at least up to 40 GHz. These results show monolayer is natural multiplier.

We present the modeling and measurements of microwave propagation in a coplanar waveguide over graphene range frequencies 40 MHz-110 GHz, which suggest that could work well very large bandwidth. Graphene is acting as natural matching device because its equivalent resistance at these able to vary more than 75% when DC biases are applied −4 V 4 on waveguide.

This letter describes the fabrication and morphological microwave characterization of film bulk acoustic resonator structures, supported on very thin GaN membranes. We have demonstrated, by employing both white-light profilometry as well X-ray diffraction, low deflection stress membranes supporting metallization. Using test structure two FBAR structures connected in series, a floating backside metallization, we obtained resonance frequencies 6.3 GHz for 0.5-mum-thick membrane. The quality...

This letter describes the manufacture and characterization of surface acoustic wave (SAW) devices on GaN/Si devoted to applications above 5-GHz frequency range. The SAW structures consist two face-to-face interdigitated transducers (IDTs), placed at different distances. Using a TiAu metallization, 80-nm-thick advanced e-beam lithographical techniques with IDTs fingers spacings 200 nm wide have been obtained GaN layer. On wafer measurement <i xmlns:mml="http://www.w3.org/1998/Math/MathML"...

This paper presents the fabrication processes for micromachined millimetre-wave devices, on two different types of semiconductor substrates. The first process uses micromachining high-resistivity < 100> oriented silicon. A three-layer dielectric membrane, with a total thickness 1.5 µm is used as support structures. was manufacturing coupled line filters, central operating frequencies 38 and 77 GHz, respectively. second based GaAs micromachining. For time, 2.2 thin GaAs/AlGaAs obtained by...

This paper addresses for the first time design, fabrication and ‘on wafer’ characterisation of membrane supported Yagi–Uda coplanar waveguide fed antenna structures, operating in 45 GHz frequency range. The antennae were fabricated on 1.4 μm thin SiO2/Si3N4 membranes obtained by micromachining high resistivity silicon, using a backside reactive ion etching process. approach has assured almost free-space conditions dry process allowed effect bulk silicon wall that supports main radiation...

The letter presents the investigation of temperature dependence charging mechanism dielectric layer in radio frequency microelectromechanical system switch. accumulated charge kinetics are monitored through transient response device capacitance when a bias greater than pull-in is applied. shown to follow stretched exponential law. “time scale” process found be thermally activated, with an activation energy that determined from Arrhenius plot.

The fabrication and characterisation of surface acoustic wave resonators operating in the gigahertz frequency range are presented. devices were fabricated on thin AlN layers deposited by magnetron sputtering high resistivity (100) oriented silicon substrates. Using direct writing e-beam lithography, well defined interdigital transducers with 300 nm finger width spacing have been obtained. On-wafer microwave measurements demonstrated a narrow bandstop characteristic rejection at approximately...

This letter proposes a spherical 3-D Smith Chart suitable for representing both active and passive microwave circuits. Using the mathematical concept of Riemann sphere, extended reflection coefficient plane is transformed into surface unit sphere. Since proposed compiles whole complex plane, all possible loads are included. A simple graphic tool thus obtained that successfully unifies In addition, lossy lines with characteristic impedances can also be represented. The presents Chart,...

This paper reports on a GaN/Si surface acoustic wave (SAW) impedance element filter operating in the few gigahertz region. The PI-type consists of three SAW resonators with same digit/interdigit widths, integrated series/parallel planar inductors. design procedure is based modeling using four parameters, independent equivalent circuit model representation (series resonance frequency, static capacitance, quality factor, and effective coupling coefficient). series frequency tuned by inductor...

The design and realisation of original millimetre-wave tunable bandstop filters using MEMS (micro-electro-mechanical-systems) technology for applications is presented. behaviour achieved by switches. overall structures, including the switches, have been manufactured dielectric membrane in order to minimise losses. Experimental validations are reported validate proposed topology: frequency shifted approximately 3.5 GHz V-band when switches actuated.

GaN is a wide-bandgap semiconductor with still unexplored capabilities for ultraviolet detection. To exploit properties better detection, metal-semiconductor-metal-type photodetector structure was designed and manufactured on 2.2 microm thin membrane fabricated by micromachining techniques. As result, very low dark current (30 pA at 3 V) maximum responsivity of 14 mA/W wavelength 370 nm were obtained.

We report on measurements and modeling of a new physical effect in graphene, which consists oscillations the current-voltage characteristic measured between wide contacts patterned across graphene flake. The origin this is carrier transport dependence two spatial components wave vector, that becomes evident for affects transmission ballistic electrons, similar to case non-normal incidence.

The dc and microwave experiments on a top-gate field effect transistor based graphene, at far from the Dirac point, are reported. Far point behaves as an active device, while becomes passive its amplification being suppressed due to reduction in carrier density. Microwave switches can be implemented using this property. maximum stable gain of is preserved up 5 GHz.

This paper presents the design, fabrication and millimeter wave measurements of a w-band (75-110 GHz) hybrid integrated micromachined receiver. an double-folded slot antenna has been manufactured using silicon micromachining techniques. The receiver includes flip chipped diode, which is used as detector modulator to demonstrate identification (MMID) system. experimental 77 GHz results show, that backscattering based communication in radio frequency (RFID feasible also range.

In this paper we present, for the first time, a X band slot antenna with shorted graphene patch. The patch is biased through signal and ground of coplanar waveguide feed. change in electric field determines impedance sheet, leading to tuning behavior. 3D electromagnetic design simulation will be presented. structures were fabricated on high-resistivity silicon 0.3 μm thick oxide layer single sheet deposited by Graphenea. experimental results are good agreement simulations show tunability...

In this paper, we describe the design, manufacturing and characterization of a monolithically integrated micromachined millimeter-wave receiver module. The antenna array, matching network, GaAs Schottky diode are supported on thin membrane. structure benefits from advantages membrane transmission lines as well integration 2.2 μm membranes were grown by molecular beam epitaxy formed reactive ion etching employing selective etch-stop techniques. results measurements voltage sensitivity...

This paper reports on microwave characteristics of micromachined GaN-based thin-film bulk acoustic resonator devices. The 2.2 micron active piezoelectric layer was epitaxially grown (111)-oriented high-resistivity silicon substrate. Bulk micromachining techniques were used for the release resonating GaN membrane structure. S-parameter measurements have shown a fundamental mode resonance around 1.3 GHz. Extracted material parameters such as an velocity 5700 m/s and effective coupling...

Membrane GaN metal–semiconductor–metal (MSM) photodetector structures using nanolithographic techniques have been manufactured for the first time. Very low dark currents and unexpected high values responsivity obtained. It seems that membrane together with (submicronic) MSM structure increase gain of responsivities in range 50–100 A/W can be