Stretchable and compliant electrodes on polydimethylsiloxane (PDMS) are efficiently fabricated by the implantation of neutral metallic clusters aerodynamically accelerated by a supersonic expansion. The production of these nanocomposite electrodes avoids any charging or carbonization of PDMS and the electrodes can withstand many deformation cycles, decreasing their resistance upon cyclical stretching. Micrometric patterns can be simply fabricated by stencil mask patterning.

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We fabricated highly adherent and electrically conductive micropatterns on SU-8 by supersonic cluster beam deposition (SCBD). This technique is based on the acceleration of neutral metallic nanoparticles produced in the gas phase. The kinetic energy acquired by the nanoparticles allows implantation in a SU-8 layer, thus producing a metal-polymer nanocomposite thin layer. The nanocomposite shows ohmic electrical conduction and it can also be used as an adhesion layer for further metallization with a metallic overlayer. We characterized the electrical conduction, adhesion and biocompatibility of microdevices obtained by SCBD on SU-8 demonstrating the compatibility of our approach with standard lift off technology on 4'' wafer. A self-standing and flexible Micro Electrode Array has been produced. Cytological tests with neuronal cell lines demonstrated an improved cell growth and a spontaneous confinement of cells on the nanocomposite layer.

Stretchable and conformable optical devices open up very exciting perspectives for the fabrication of systems incorporating diffracting and optical power in a single element. Supersonic cluster beam implantation of silver nanoparticles in an elastomeric substrate grooved by molding allows effective fabrication of cheap and simple stretchable optical elements able to withstand thousands of deformations and stretching cycles without any degradation of their optical properties. The nanocomposite‐based reflective optical devices were characterized both morphologically and optically showing excellent performances and stability compared to similar devices fabricated with standard techniques. The nanocomposite‐based devices can therefore be applied to arbitrary curved nonoptical grade surfaces in order to achieve optical power and to minimize aberrations like astigmatism. The high resilience of the nanocomposite material on which the devices are based allows them to be peeled and reused multiple times.

We demonstrate the fabrication of gold-polydimethylsiloxane nanocomposite electrodes, by supersonic cluster beam implantation, with tunable Young's modulus depending solely on the amount of metal clusters implanted in the elastomeric matrix. We show both experimentally and by atomistic simulations that the mechanical properties of the nanocomposite can be maintained close to that of the bare elastomer for significant metal volume concentrations. Moreover, the elastic properties of the nanocomposite, as experimentally characterized by nanoindentation and modeled with molecular dynamics simulations, are also well described by the Guth-Gold classical model for nanoparticle-filled rubbers, which depends on the presence, concentration, and aspect ratio of metal nanoparticles, and not on the physical and chemical modification of the polymeric matrix due to the embedding process. The elastic properties of the nanocomposite can therefore be determined and engineered a priori, by controlling only the nanoparticle concentration.