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In this article, we describe L-UTSOI, a standard compact model dedicated to FD-SOI technologies, built to describe accurately the device characteristics in all bias configurations. Used in industrial Process Design Kits for years, L-UTSOI is a highly mature model and its strong physical background makes it the best in-class solution for current and future FD-SOI technology applications.

We present a nanofabricated Thermal Conductivity Detector (nano-TCD), designed to be monolithically integrated with a CMOS technology compatible NEMS, in order to widen its analyte spectrum in the low molecular weight volatile organic compounds range. The nano-TCD uses arrays of silicon nano-wires, with 220 nm × 250 nm cross sections and 2 μm suspension gap over the silicon bulk. In order to filter out the 1/f flicker noise produced by the silicon nanowires, we used a signal modulation technique based on the 3ω method, thanks to the fast response time of the nano-TCD. Experimental results demonstrate detection of pentane and butane with a limit of detection of 60 ppm and 70 ppm respectively (mole fraction).

In this work, a comprehensive, predictive and quantitative model of a whole gas analyzer is provided in order to facilitate the design of such high performance devices. All the pre-analytical (gas separation) and analytical (detection and readout) stages have been modeled and experimentally calibrated. Heterogeneous simulations have been used to quantify the impact of the whole architecture on the output characteristic of the gas analyzer. Finally, the model of the NEMS sensor and the chromatography micro-column assembly has been experimentally validated with TEOX (toluene, ethylbenzene, octane, and xylene) gases.

In this paper, we compare several materials that can be used as sacrificial and etch stop layer for 3D NEMS-CMOS co-integration. During these last 10 years Very Large Scale Integration techniques, well developed for transistors, have been used for the M/NEMS world (Micro/Nano Electro-Mechanical Systems). This allowed the construction of various kinds of miniaturized nano-sensors, especially resonators that can be used for gas sensing, mass spectrometry and molecules recognition for example [1,2]. Nevertheless, the use of such nano-sensors requires a CMOS electronic circuit for the readout part and for the oscillating-loop creation with the nano-resonator. The CMOS part can be on a separated die linked to the NEMS resonator using wire bonding connections (Fig.1-a). However, in order to reduce signal transmission loss and allows the fabrication of a sensor with a high density of resonator, the best approach consists in processing both NEMS and CMOS on the same die (Fig.1-b and c) [3,4], in particular following a 3D scheme (Fig.1-c) [5,6]. The NEMS release process, commonly performed by a HF (Hydrogen Fluoride) vapor etching operation, is the final step of the integration. It implies the selection of two kinds of materials. The first one is a sacrificial layer in order to achieve a well-controlled and clean release of the mechanical structure. The second one is an etch stop layer located between the NEMS and CMOS for protecting all the area under the nano-resonator (Fig.2). In such 3D approach, etch stop and sacrificial layers can be deposited at high temperature before the molecular bonding of the mechanical part with the electronic part. Two parameters are critical for the selection of those materials; the etch rate and the presence and dimensions of the residues (see Fig.3, 4, 5 and 6) which may result from a silicon-fluorine complex precipitation during the etching process [7]. These residues must not disturb the mechanical resonator during its oscillations. This paper will present results about etch-rates and residual dimensions on HF vapor etching of materials used for the NEMS realization. It is shown in Fig.3 and Fig.6 that USG (Undoped Silicon Glass) and SiH4, usually used in back-end processes, are not suitable for the vapor HF release contrary to TEOS (tetraethyl-orthosilicate) Low Rate (LR) and boron-nitride (BN). Our study shows that the latter constitutes a good etch stop layer for HF vapor processing within a 3D integration scheme. [1] J. Arcamone et al, IEDM 2011 IEEE International, pp.29.3.1, 29.3.4, 5-7 Dec. 2011 [2] Y.T. Yang et al, Nano lett., Vol. 6, No. 4, Apr. 2006 [3] E.Ollier et al, MEMS 2012 [4] J. Arcamone et al, Tech. Digest. IEDM 2012, pp. 15.4.1-15.4.4 [5] P.Batude et al, J.Emerging Sel. Top.Circuits Syst, Vol.2, No.4, Dec. 2012 [6] J-C. Souriau, IEEE Trans. Compon., Packag. Manuf. Technol. Vol. 1, No.6, June 2011 [7] H. Ritala et al, ECS Trans. 2009 25(5): 355-358

We report a novel NEMS-based heterodyne self-oscillator. By using a downmixing detection scheme, the NEMS motion piezoresistive signal at 20 MHz is shifted down to few tens of kHz, thus avoiding the negative impact of stray capacitances. This technique allows the NEMS self-oscillator to benefit from its major advantages: a high dynamic range and a high signal to background ratio. However in this form, the signal cannot be directly inserted in a standard oscillator feedback loop since the output signal is neither proportional, nor at the same frequency as the NEMS actuation signal. This paper describes a novel heterodyne architecture so that self-oscillation motion of the NEMS builds up with excellent frequency stability. By providing a high dynamic range and high signal to background ratio, this feedback loop architecture represents an efficient way to track NEMS resonance frequency in real time, as required in sensing applications like mass sensors.

3-D sequential integration stands out from other 3-D schemes as it enables the full use of the third dimension. Indeed, in this approach, 3-D contact density matches with the transistor scale. In this paper, we report on the main advances enabling the demonstration of functional and performant stacked CMOS-FETs; i.e., wafer bonding, low temperature processes (

This work presents a technique to cancel the parasitic feedthrough current in a fully CMOS integrated electrostatic micromechanical resonator. A four-electrode balanced topology has been proven to enhance the measured response of a polysilicon clamped-clamped beam resonator. The test results obtained show a pure RLC behavior of the resonator at 10.98MHz.

The emergence of MEMS in consumer applications has dramatically increased market perspectives but also puts very strong constraints on cost and integration issues. Addressing these issues through further size reduction is not always relevant as it does not allow maintaining a correct signal to noise ratio (SNR) for the ubiquitous capacitive MEMS sensors. Different solutions are presented here according to the nature of the signal to be sensed: For physical sensors a new concept mixing a micron sized proof mass and a nano-sized detection structure is described. For chemical sensors, the reduction in size actually presents some advantages in terms of high resonant frequency, reduced gas damping, and high sensitivity to applied forces or added mass. Application of nano-resonators to gaz sensing is depicted.

These last 10 years, smaller, less expensive, and higher performance sensors are required for gas sensing applications. To date no true detection principle has been recognized as the best candidate for such application. Microsytems or Micro/Nano Electro Mechanical Systems (M/NEMS) used as gravimetric detectors are among the probable candidates. The technology can indeed be manufactured en masse and can provide multi-gas analysing platform. In this paper, we present a comprehensive overview of micro/nano sensors based on the gravimetric effect to detect an absorbed gas on top of their surfaces. The paper provides a comparison between different electromechanical devices (Bulk Acoustic Wave, Surface Acoustic Wave, Capacitive Micro-machined Ultrasonic Transducer, Micro/Nano cantilevers) with an introduction to gas adsorption mechanisms, material selection, detection principles and design guidance useful to researchers or engineers.

The paper reports on an integrated device combining a single-crystal silicon NEMS with an embedded MOS transistor in transconductance configuration fabricated with a simple and low cost technology based on localized Silicon on Nothing technology. Thanks to the high transconductance achievable, this approach enables NEMS with embedded MOS transistors for enhanced readout efficiency.

We present the evaluation of the damage induced on CMOS circuits when exposed to electron- and ion-beams. The experiments are performed by localized exposure of selected areas of the CMOS circuit and surrounding specific sites. Electrical characterization analysis is performed on line, by in situ contacting the circuit during the exposure experiments. The analysis of the experimental results shows up the importance of the localization of the exposure, and mainly of the beam energy of the electrons. From the analysis, optimal exposure conditions are defined to attempt the fabrication of monolithically integrated nanomechanical devices into CMOS circuits (CMOS-NEMS) by electron-beam lithography or ion beam lithography. Examples of these fabrication approaches are shown.

We report on a recently developed liquid nanodispensing technique (NADIS) using an atomic force microscope probe with an aperture at its apex, to deposit nanodroplets with volumes in the femto- to atto-liter range on a surface. Besides its potential applications in terms of nanopatterning, NADIS is also an efficient tool for studies on wetting at micro to nanometer scale. We illustrate this point by the monitoring of the evaporation of femtoliter sessile droplets using a nanomechanical mass sensor.

This brief presents a fully integrated nanoelectromechanical system (NEMS) resonator, operable at frequencies in the megahertz range, together with a compact built-in CMOS interfacing circuitry. The proposed low-power second-generation current conveyor circuit allows detailed read-out of the nanocantilever structure for either extraction of equivalent circuit models or comparative studies at different pressure and dc biasing conditions. In this sense, extensive experimental results are presented for a real mixed electromechanical system integrated through a combination of in-house standard CMOS technology and nanodevice post-processing by nanostencil lithography. The proposed read-out scheme can be easily adapted to operate the nanocantilever in closed loop operation as a stand-alone NEMS oscillator.

NEMS based sensors open several opportunities for integrated solutions in emerging domains as chemical analysis and life science. With critical dimensions ranging between 10 and 100 nm, those devices can be made at the VLSI scale, possibly co-integrated with CMOS and are well suited for autonomous, highly sensitive or dense sensors. Several applications will be presented, as complex gas portable recognitions systems, mass spectrometry, or bio-sensors.

Micro/nanomechanical resonators have been designed and fabricated with the aim to be used as distributed mass sensors for in situ measurement of the thickness of ultra-thin layers. First, we present a comparative study of three kinds of oscillating devices (cantilever, bridge and quad beam). The quad beam design has been selected for fabrication because it combines high sensitivity and good electrical response. The complete fabrication process of the device is based on electron beam lithography, lift-off and reactive ion etching. The frequency response has been characterized by means of electrical excitation and capacitive read-out.

In this work, we studied the effect of the deposition temperature, partial pressure and crystallite texture on the poly/epi growth rate ratio by decomposition of silane. Deposition was performed by rapid thermal chemical vapor deposition (RTCVD) in the temperature range 590

Linear scaling CMOS has encountered many hurdles which request new process modules, driven mainly by the maximization of energy efficiency. Fabrication at the sub 10nm node level will request Intrinsic Variability approaching to zero. The rapid growth of mobile, multifunctional and autonomous systems is hardly demanding to reach Zero Power consumption. The solutions to integrate Thin Film based devices, architectures and systems in order to face these challenges are described.

This paper reviews the last major realizations in the field of monolithic integration of NEMS with CMOS. This integration scheme not only drastically improves the efficiency of the electrical detection of the NEMS motion. Our analysis is that it also represents a compulsory milestone to practically implement breakthrough applications of NEMS, such as mass spectrometry, that require large capture cross section (VLSI-arrayed NEMS) and individual addressing (co-integration of NEMS arrays with CMOS for closed-loop operation).

This work reports on top-down nanoelectromechanical resonators, which are among the smallest resonators listed in the literature. To overcome the fact that their electromechanical transduction is intrinsically very challenging due to their very high frequency (100 MHz) and ultimate size (each resonator is a 1.2 μm long, 100 nm wide, 20 nm thick silicon beam with 100 nm long and 30 nm wide piezoresistive lateral nanowire gauges), they have been monolithically integrated with an advanced fully depleted SOI CMOS technology. By advantageously combining the unique benefits of nanomechanics and nanoelectronics, this hybrid NEMS-CMOS device paves the way for novel breakthrough applications, such as NEMS-based mass spectrometry or hybrid NEMS/CMOS logic, which cannot be fully implemented without this association.

We report on the first experimental demonstration of a self-oscillator based on a single-crystal silicon NEMS resonator monolithically co-integrated with a CMOS circuitry. The latter, composed only by seven transistors, is manufactured with a very low-cost 0.35μm technology. The NEMS-CMOS self-oscillator pixel is as small as 50×70 μm2 (pads excluded) and can oscillate near 8MHz. In this paper are described the NEMS-CMOS oscillator characteristics and the implementation method of the self-oscillating loop.

This work reports on the realization of the smallest Pirani gauge ever, based upon highly-doped silicon nanowires. This paper details the fabrication process and the characterization of the thermal properties of Si nanowires, such as thermal conductivity and thermal coefficient of resistivity for various working temperatures in the 300K-700K range. A dynamic transduction technique, based on the 3-omega measurement is described and the device performances (i.e. sensitivity and signal-to-noise ratio) are measured. With the tested devices a resolution below 5%/Hz1/2 is obtained in the 0.1mbar-1bar range.

International audience; The purpose of this paper is to provide a simple framework for determining the resonant pull-in of MEMS oscillators, either parallel-plate, CC-beam or cantilever, under one- sided and two-sided sinusoidal, square-wave or pulse- actuation. Furthermore, the values of the resonant and static pull-in amplitudes are calculated and tabulated, in all the considered cases.

This work constitutes the first demonstration of monolithic integration of single-crystal silicon capacitive NEMS resonators with CMOS. With this approach, the efficiency of the electrical detection of the NEMS motion is outstanding and achieved with only seven transistors that are fabricated with a completely unmodified and very low-cost 0.35μm bulk CMOS technology.

In this paper, we will present some possible emerging applications for Nano-Electro-Mechanical Systems (NEMS) and the interest of their co-integration with CMOS. We will compare some integration schemes and present mass sensing as a possible emerging application. In particular, experimental results on complex gas measurements with NEMS will be introduced. We will show that multi-physics simulations and compact modelling of NEMS components (including chemical and physical effects) can be efficiently used in circuit simulations standard tools for such system optimization.

Similar to transistors, the size of MEMS components is continuously shrinking, progressing from MicroElectroMechanical Systems to NanoElectroMechanical Systems (NEMS). Indeed, NEMS are emerging as a new field of interest because their submicron dimensions make them converge towards CMOS fabrication processes. They have specific advantages such as fast response time and high detection sensitivity when used as a resonant sensor [1]. From the application point of view, NEMS interact “naturally” with the nanoscale world and can sense unprecedented physical and biological phenomena, such as the mass of a single molecule, the force exerted by living cells or certain biochemical reactions. In the next five to ten years, NEMS should offer a real breakthrough for mass spectrometry or gas analysis applications because they can achieve similar resolution to conventional lab equipment but at a lower cost due to their compatibly with VLSI processes.

This paper reports on ultra-scaled single-crystal Si NEMS resonators (25–40nm thick) operating in the 10–100MHz frequency range. Their first monolithic integration at the front-end level with CMOS enables to extract the signal from background leading to possible implementation of direct/homodyne measurement, for high sensitivity sensing applications and portable systems.

ISBN: 978-1-4577-0506-9; International audience; This work demonstrates for the first time a VLSI-compatible nano/microfabricated, high-performance, portable multi-gas analyzer associating gas chromatography and NEMS resonators.