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A new magnetic micro-actuator with integrated permanent magnets has been developed. The design of this device with a levitating mobile magnet is a real innovation and is patented. The structure was modeled using analytical and numerical calculations. Furthermore, the fabrication feasibility, using collective micro-technology processes, has recently been demonstrated.

A reflectarray element with electronic phase control implemented by ohmic MEMS switches is characterized and validated in the X-band. The proposed element is based on two patches aperture-coupled to a microstrip network with a common delay line, forming a sub-array, in order to reduce both cost and manufacturing complexity in large reflectarrays. The electrical length of the line can be modified through the inclusion of a series switch between different segments of the microstrip line. The ohmic electrostatic switch has been designed for RF applications and manufactured on a coplanar line. The transition between the coplanar line of the MEMS and the microstrip delay line has been implemented using gold wires which have been bonded to the printed pads. This connection leads to a high impedance line. The MEMS switches have been characterized using reflection and transmission measurements on microstrip lines for deducing an equivalent circuit, which has been used in the validation of the gathered element with electronic phase control measured using waveguide simulator. The same approach has been applied to evaluate a 2-bit reflectarray element.

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This paper reports on the electrodeposition at room temperature and the characterization of hard magnetic CoPtP material. An acidic bath has been set up to be compatible with the use of photoresist for micro technologies processes. X-ray diffraction (XRD) diagrams show that CoPtP alloy crystallizes in the hexagonal system. The film growth is generally columnar with a pronounced ⟨0 0 2⟩ texture associated with preferential out-of-plane magnetization. Using particular electrodeposition conditions, in-plane magnetization can be recovered and coercivities as high as 2800 Oe are reached for patterned layers. So a room temperature electroplating process able to produce patterned micromagnets usable in magnetic applications has been set up. Examples of the integration of CoPtP micromagnets are described through the fabrication of three devices: a multilayered giant magneto-resistive sensor biased by five electroplated magnets, a vertical magnetic bistable microactuator and a horizontal magnetic bistable microswitch. The main challenge for the last two devices was to demonstrate the actuation of a moving micromagnet without any mechanical guiding during commutation. The demonstrated bistability provided by the use of micromagnets emphasizes the interest in these devices for many applications.

For its outstanding piezoelectric coefficients, thinfilm sol-gel Pb(Zr 0.52 , Ti 0.48 )O 3 (PZT) has been widely studied over the past few decades. In particular, the impact of Zr/Ti ratio control on e 31,eff coefficient has been investigated at low fields. Yet, when it comes to actuation, PZT films are used with electric fields higher than the coercive field. In this paper, the influence of Zr/Ti gradient reduction on e 31,eff coefficient is investigated in actuating conditions, ie under high fields.

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