Samer Houri

imec · Sensors and Actuators

The ultimate goal of this research proposal is the creation of a micro-optomechanical intelligence. The proposal centers on the development and investigation of very large-scale integrated (VLSI) arrays of coupled M/NEMS devices as platforms for the experimental study of nonlinear dynamics of high-dimensional systems. The potential of VLSI M/NEMS a...

This work presents a frequency multiplexed 3-limit cycles network in a multimode microelectromechanical nonlinear resonator. The network is composed of libration limit cycles and behaves in an analogous manner to a phase oscillator network. The libration limit cycles, being of low frequency, interact through the stress tuning of the resonator, and...

We present a mode of operation for Duffing-type nonlinear microelectromechanical system devices whereby a self-sustained multifrequency output is generated. This self-sustained librator regime creates a limit cycle around a dynamical fixed point, i.e., around fixed points within the rotating frame, whereas a traditional oscillator generates a limit...

We present a novel mode of operation for Duffing-type nonlinear microelectromechanical (MEMS) devices whereby a self-sustained multi-frequency output is generated. This new librator regime creates a limit cycle around a dynamical fixed point, i.e. around fixed points within the rotating frame, whereas a traditional oscillator generates a limit cycl...

Using a coupled parametric resonator array for generating and propagating a topological soliton in its rotating-frame phase space is theoretically and numerically investigated. In an analogy with the well-known ϕ4 model, the existence of a soliton is topologically protected, as the boundary of two different phase domains of parametric oscillation....

Using a coupled parametric-resonator array for generating and propagating a topological soliton in its rotating-frame phase space is theoretically and numerically investigated. In an analogy with the well-known phi4 model, the existence of a soliton is topologically protected as the boundary of two different phase domains of parametric oscillation....

This Letter provides a low-power method for chaos generation that is generally applicable to nonlinear micro- and nanoelectromechanical systems (MNEMS) resonators. The approach taken is independent of the material, scale, design, and actuation of the device in question; it simply assumes a good quality factor and a Duffing type nonlinearity, featur...

This work provides a low-power method for chaos generation which is generally applicable to nonlinear M/NEMS resonators. The approach taken is independent of the material, scale, design, and actuation of the device in question; it simply assumes a good quality factor and a Duffing type nonlinearity, features that are commonplace to M/NEMS resonator...

We investigate the dynamics of a microelectromechanical self-sustained oscillator supporting multiple resonating and interacting modes. In particular, the interaction of the first four flexural modes along with the first torsional mode are studied, whereby 1:2, 1:3, and 2:1 internal resonances occur. Even and odd modes are induced to couple by brea...

We investigate the dynamics of a microelectromechanical (MEMS) self-sustained oscillator supporting multiple resonating and interacting modes. In particular, the interaction of the first four flexural modes along with the first torsional mode are studied, whereby 1:2, 1:3, and 2:1 internal resonances occur. Even and odd modes are induced to couple...

The aim of this work is to theoretically investigate the possibility of Kerr frequency combs in mechanical systems. In particular, whether microelectromechanical devices (MEMS) can be used to generate frequency combs in a manner that is analogous to the optical frequency combs generated in optical microresonators with Kerr-type nonlinearity. The an...

A micro-electromechanical systems (MEMS) Duffing resonator is driven by two adjacent frequency tones into the nonlinear regime. We show that if the two-tone drive is applied at a frequency where a bistable response of the nonlinear oscillator exists, then the system output will be modulated by a relaxation cycle caused by periodically jumping betwe...

This work investigates the behavior of an AlGaAs/GaAs piezoelectric nonlinear MEMS oscillator exhibiting a 1:3 internal resonance. The device is explored in an open-loop configuration, i.e., as a driven resonator, where depending on the drive conditions we observe energy transfer between the first and third modes, and the emergence of supercritical...

The aim of this work is to theoretically investigate the possibility of Kerr frequency combs in mechanical systems. In particular, whether microelectrome-chanical devices (MEMS) can be used to generate frequency combs in a manner that is analogous to the optical frequency combs generated in optical microresona-tors with Kerr-type nonlinearity. The...

Stochastic switching between the two bistable states of a strongly driven mechanical resonator enables detection of weak signals based on probability distributions, in a manner that mimics biological systems. However, conventional silicon resonators at the microscale require a large amount of fluctuation power to achieve a switching rate in the ord...

Stochastic switching between the two bistable states of a strongly driven mechanical resonator enables detection of weak signals based on probability distributions, in a manner that mimics biological systems. However, conventional silicon resonators at the microscale require a large amount of fluctuation power to achieve a switching rate in the ord...

This work investigates the behavior of an AlGaAs/GaAs piezoelectric nonlinear MEMS oscillator exhibiting a 1:3 internal resonance. The device is explored in an open-loop configuration, i.e. as a driven resonator, where depending on the drive conditions we observe energy transfer between the first and third modes, and the emergence of supercritical...

A MEMS Duffing resonator is driven by two adjacent frequency tones into the nonlinear regime. We show that if the two-tone drive is applied at a frequency where a bistable response of the nonlinear oscillator exists, then the system output will be modulated by a relaxation cycle caused by periodically jumping between the two solution-branches of th...

Graphene, the carbon monolayer and 2D allotrope of graphite, has the potential to impact technology with a wide range of applications such as optical modulators for high-speed communications. In contrast to modulation devices that rely on plasmonic or electronic effects, MEMS-based modulators can have wider tuning ranges albeit at a lower operating...

In the field of nanomechanics, parametric excitations are of interest since they can greatly enhance sensing capabilities and eliminate cross-talk. Above a certain threshold of the parametric pump, the mechanical resonator can be brought into parametric resonance. Here we demonstrate parametric resonance of suspended single-layer graphene membranes...

Hexagonal boron nitride is a 2D material whose single-layer allotrope has not been intensively studied despite being the substrate for graphene electronics. Its transparency and stronger interlayer adhesion with respect to graphene makes it difficult to work with, and few applications have been proposed. We have developed a transfer technique for t...

In the field of nanomechanics, parametric excitations are of interest since they can greatly enhance sensing capabilities and eliminate cross-talk. However, parametric excitations often rely on externally tuned springs, which limits their application to high quality factor resonators and usually does not allow excitation of multiple higher modes in...

We use a scalable optical technique to characterize more than 21000 circular nanomechanical devices made out of suspended single- and double-layer graphene on cavities with different diameters (D) and depths (g). To maximize the contrast between suspended and broken membranes we used a model for selecting the optimal color filter. The method enable...

Thermal properties of suspended single-layer graphene membranes are investigated by characterization of their mechanical motion in response to a high-frequency modulated laser. A characteristic delay time $\tau$ between the optical intensity and mechanical motion is observed, which is attributed to the time required to raise the temperature of the...

We explore the dynamics of a graphene nanomechanical oscillator coupled to a reference oscillator. Circular graphene drums are forced into self-oscillation, at a frequency fosc, by means of photothermal feedback induced by illuminating the drum with a continuous-wave red laser beam. Synchronization to a reference signal, at a frequency fsync, is ac...

Previous statistical studies on the mechanical properties of chemical-vapor-deposited (CVD) suspended graphene membranes have been performed by means of measuring individual devices or with techniques that affect the material. Here, we present a colorimetry technique as a parallel, non-invasive, and affordable way of characterizing suspended graphe...

We demonstrate thermo-mechanical relaxation oscillations in a strongly driven quartz crystal. Dynamic bifurcation leads to two stable oscillation states with a distinct electrical impedance. Slow Joule-heating, which shifts the susceptibility of the crystal, provides a feedback that leads to thermally-induced oscillations, in which the amplitude of...

The influence of the power-clock generator on the global energy-performance relationship of nanoelectromechanical (NEM) switch-based quasi-adiabatic logic circuits is investigated in this paper. This investigation is undertaken the capacitor bank type generator, it is found that the leakage current of the MOSFET switching devices used within the ge...

In this paper, a detailed analysis and comparison of nanoelectromechanical systems (NEMS) and CMOS technologies for low power adiabatic logic implementation is presented. Fundamental limits of CMOS-based adiabatic logic are identified. Analytic relations describing the energy-performance for sub-threshold adiabatic logic are also explicitly derived...

The design of an MEMS frequency up-converter is described in this paper, The device consists of two electrostatically coupled resonators that relies on the hysteresis of electrostatic pull-in in order to multiply the input excitation frequency by a significant factor, possibly up to several orders of magnitudes in order to increase the efficient of...

This paper qualitatively explores the performance limits, i.e., energy vs. frequency, of adiabatic logic circuits based on nanoelectromechanical (NEM) switches. It is shown that the contact resistance and the electro-mechanical switching behavior of the NEM switches dictate the performance of such circuits. Simplified analytical expressions are der...

In this paper, a detailed comparison between the expected performance of CMOS-based and nanoelectromechanical systems (NEMS) based adiabatic logic circuits is presented. The modeling of the NEMS devices is done using a 1-dimensional reduced order model (1d ROM) of the electromechanical switches. This model will give an honest analytical depiction o...

The performance envelope, i.e. energy vs. frequency, of adiabatic logic circuits based on nanoelectromechanical (NEM) switching elements will be explored. It will be shown that the contact resistance and the mechanical commutation time of the NEM switches dictate the performance envelope of such circuits. Approximate analytical expressions will be...

The tensile response of top-down fabricated sc-Si nanobeams is inferred from the fitting of stress-strain data obtained under tensile loading conditions over a large range of deformation. The testing is performed using MEMS structures consisting of two connected beams; a highly stressed silicon-nitride (SiN) beam connected to a sc-Si specimen beam....

Freestanding MEMS structures made of two long connected beams from different materials are fabricated and released in order to extract the stress-strain properties of thin films. The first material, named actuator, contains a high internal tensile stress component and, when released, pulls on the other beam. The strain in the beams is calculated ba...

Nanomechanical testing of silicon is primarily motivated toward characterizing scale effects on the mechanical behavior. “Defect-free” nanoscale silicon additionally offers a road to large deformation permitting the investigation of transport characteristics and surface instabilities of a significantly perturbed atomic arrangement. The need for dev...

A fabrication process to characterize single crystalline silicon microbeams under uniaxial tension is presented. The microbeams subjected to an uniaxial tensile stress are released without stiction owing to a critical point drying step. Based on the deformation measured by scanning electron microscopy images, the corresponding strain and stress are...

Export Date: 3 April 2012, Source: Scopus, Art. No.: 5556353

This paper presents a complete study of the impact of mechanical stress on the performance of SOI MOSFETs. This investigation includes dc, analog and RF characteristics. Parameters of a small-signal equivalent circuit are also ex-tracted as a function of applied mechanical stress. Piezore-sistance coefficient is shown to be a key element in describ...

The measurement of the mechanical properties of submicron sized specimens is extremely challenging due to difficulties for manipulating samples, for applying small load and for extracting accurate stresses and strains. A novel, versatile concept of micromachines has been developed to measure the mechanical response, up to large strains and fracture...