A low cost and low temperature thin film packaging process based on the transfer of an electroplated Nickel 3D cap is proposed. This process is based on adhesion control of a thick molded cap Ni film on the carrier wafer by using a plasma deposited fluorocarbon film, on mechanical debonding and on adhesive bonding of the microcaps on the host wafer with BCB sealing rings. Mechanical characterizations show that the transferred microcaps have a high stiffness, a low stress and a high adhesion. Because this process is simple and only involves a low temperature (250°C) heating of the host wafer, it is highly versatile and suitable for the encapsulation of micro and nano devices, circuits and systems elaborated on a large range of substrate materials.

Electrodeposition process was studied in order to obtain uniformly thick magnetic films which could be incorporated in magnetic microsensors and actuators. Ni and NiFe patterns of different dimensions were deposited by micromolding on a Cu/Ti seed layer sputtered on SiO 2 /Si (for NiFe) and glass (for Ni). In the case of NiFe deposit, a linear deposition rate was calculated by measuring the deposit thickness using mechanical profilometry. The optimum pattern composition for the fabrication of magnetic microdevices was 80 at.% of Ni, that was found by comparing the magnetic properties of the deposits obtained from different conditions. The deposits structure was also characterized. All the parameters were studied as a function of the current density so that by controlling the electrodeposition conditions the characteristics of the deposits could be controlled. NiFe films were integrated in multilayered magneto-impedance sensors. They present good adherence of the layers even after performing annealing at both 300 • C and 500 • C and sensor sensitivity reaches 1%/Oe.

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