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The paper describes a new architecture of a Safe Arm and Fire device (SAF) that could constitute a real breakthrough for safe miniature fuzing device. On the one hand, it takes all the functions embodied in a conventional mechanical arm and fire system and integrates them in a single 1 cm 3 package made of assembly of different parts. On the other hand, for the first time, it combines a mechanical arming unit with electrical safety functionalities on the same silicon initiator's chip. It respects the STANAG 4187 norm (1 A/W during 5 min of not fire) and requires only 635 mW for ignition. The paper presents the design, fabrication and test of one miniature SAF device integrating a micropyrotechnical actuation.

We propose a safe, arm and fire (SAF) device that could constitute a real breakthrough for safe miniature fuzing device. It integrates all the functions of a conventional mechanical arm and fire system and integrates them within 1 cm 3 . For the first time, it combines a mechanical arming unit with electrical safety functionalities on the same silicon initiator's chip. It requires only 635 mW for ignition.

In this work, we present a novel fabrication process for the creation of lateral porous silicon membranes with tunable pore size and porosity and their integration into planar microfluidics. Since the formation of porous silicon by anodization is highly dependent on the dopant type and concentration, we use ion implantation to manipulate the local dopant concentration in order to control the membrane properties. The dead-end filtration capability of our lateral porous silicon membranes integrated within planar microchannels is demonstrated by adequately retaining 300 nm diameter beads, while molecules such as fluorescein and miRNA permeate the membranes.

International audience; Front-side connected, N-channel, normally-off, SiO2/Si3N4 chemical field effect transistor (ChemFET) microsensors have been fabricated using a standard P-well silicon technology. These ChemFETs microsensors were adapted to ammonium ion detection thanks to photosensitive polysiloxane (PSX) polymer containing nonactine as an ionophore. The ammonium-sensitive membrane has been deposited either manually by micropipette, either by spin coating and patterned using photolithography technique. Both processes have been studied and compared through the ammonium ion determination. The manually deposed layers have been characterised by thickness non-reproducibility. Therefore, spin-coated layers have good reproducibility, but their thickness of 30 µm has been responsible for an increase of the ISFET threshold voltage and a decrease of its bias current. Nevertheless, in both cases, good sensitivities have been shown on the [1 – 5] pNH4 range even if saturation phenomena have been evidenced for the lowest concentrations. These pNH4-ISFETs microsensors are developed for the monitoring of environmental pollution and more precisely for ground water analysis.

A device to study the friction of two molecularly smooth surfaces separated by an ultrathin liquid film is presented along with its design, calibration, and performance. The apparatus can move one of the surfaces and measure the friction force on the other one bidimensionally for both processes. A high mechanical impedance system (104 N/m) measures continuous friction forces where only stick–slip was previously observed. The frequency and travel distance of the movement can be varied over a wide range (frequency from 10−4 to 7 Hz and distance from 1 to 800 μm) to provide variations of the shear rate over seven orders of magnitude. The actual movement provided by piezoelectric bimorph drive can be affected by the friction forces and is measured by strain gauges. The friction forces are measured with an accuracy of ±2μN with a capacitance sensor. The mechanical design prevents the surfaces from rolling under force. The apparatus is tested with hexadecane. The potential applications of this apparatus and its...

A compact quadrifilar helix antenna is presented in the VHF band. The design and experimental validation on a low-cost realization are detailed in this paper. This design could be used on the telemetry link for the SVOM satellite project. Compared to the reference antenna, a significant height reduction of 48% is demonstrated. The measurement and simulation results reveal the capability of this design to improve slightly the naturally poor input matching of quarter wavelength quadrifilar helix antennas. A simple and low-cost manufacturing technique is also proposed to validate the design.

This paper addresses the miniaturization of the VHF band quadrifilar helix antenna. The design and experimental validation are reported in this paper. Such a helix could be used, e.g., for telemetry link in Space-based Multi-band Variable Object Monitor satellite project. Compared to the reference quarter wavelength quadrifilar helix antenna, a significant height reduction from 48% to 62.5% is obtained. Moreover, the measurement and simulation results reveal the capability of the resulting compact antennas to improve slightly the well-known poor impedance matching of classical quarter wavelength quadrifilar helix antennas. A simple and low-cost manufacturing technique is finally detailed for validation purpose.

International audience; The packaging is an important step, allowing to transform the transducer chip into a sensor. This step is necessary to perform the sensor characterization in a real environment, while minimizing the impact of the influence parameters on the sensor response. This study concerns the impact of the packaging on the static response of a miniature pressure sensor dedicated to the monitoring of blast waves. The transducer is based on 5 µm-thick rectangular (55 µm x 135 µm) silicon membrane and piezoresistive gauges. Pressure sensitivity measurements are performed using stressed and non-stressed sensor's holder configurations. Measurements results indicate that the pressure sensitivity is doubled when the sensor's holder is stressed. Finite Element Method simulations using COMSOL Multiphysics software show here that this result originates from the deformation of the sensor's holder, which leads to the deflection of the thin silicon membrane.

Accepté 10th International Conference on the Scientific and Clinical Applications of Magnetic Carriers 10-14 june 2014 Dresden Germany; International audience; In microfluidics, the use of super-paramagnetic microparticles (SMPs) has experienced a dramatic increase over the last decade, but control of the magnetic field at micro scale is still a topical issue. Permanent magnets don't offer a programmable approach, external coils require a certain power, and neither are usually integrated. Hybrid systems, which include external magnets to generate a high and homogeneous magnetic field, and integrated coils that produce a high gradient, are seemingly a promising way to reach a higher precision in magnetic actuation, not mentioning the forces they create on SMPs can be attractive or repulsive. The goal of our work, for one part, is to develop a simple solution for the micro-fabrication of this kind of devices, but also to delve into the design possibilities, for instance to create a separation stage or investigate more exotic functions like focusing (without leading to a dilution or an increase in the flow rate, unlike most hydrodynamic focusing techniques).