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.

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The high specific surface of porous silicon and its high reactivity makes this material a good candidate for chemical sensors based on electrical or electromechanical devices. In this paper, several processes are presented to realize free-standing porous silicon microstructures (membranes and cantilever beams). Good resonance quality factors were measured (Q = 110 and 760 respectively) demonstrating that porous silicon is a suitable material for resonant chemical sensors.

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This paper presents a new method based on image processing (IP) for the characterization of porous silicon (PS) nanostructures. It was developed using porous silicon layers (PS1 and PS2) having different nanostructures. According to gravimetric measurements, these layers present the same porosity of 45%. First we characterized the PS layers by Barrett‐Joyner‐Halenda (BJH) theory applied to sorption data. Then applying BJH theory, we found that the mean pore diameter of PS1 and PS2 are 4.3 and 5.5 nm respectively. With Brunauer‐Emmet‐Teller (BET) theory, we found that PS1 has a specific area of 330 m2/g, and PS2 has a specific area of 223 m2/g. We obtained images of the PS layer surface by high resolution scanning electronic microscopy (HRSEM). The processing of these images leads to the estimation of mean pore diameter: 5.6 nm and 7.5 nm for PS1 and PS2 respectively, and to the representation of pore size distribution. According to a geometrical model, we estimated the porosity and found 55% and 48% for PS1 and PS2 respectively. The calculation of specific area according to the same model leads to the values of 343 m2/g and 217 m2/g for PS1 and PS2 respectively. The close agreement of results obtained by IP to those obtained by sorption theories shows the validity of our method. Advantages of images processing are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)