Development of new sticky and conducting polymer surfaces for MEMS applications

The development of new surfaces, highly sticky and conducting, is a great challenge in the field of microdevices fabrication, and more precisely for the 3D assembly of microcomponents. Such surfaces were prepared by electrochemical deposition of polyaniline films. The films prepared from a phosphoric acid solution were more adhesive than the ones obtained in other acids. Indeed, the adhesion of the polyaniline films prepared in H3PO4 was found to be high (> 1 mu N) and stable in time, as shown by AFM force measurements. The adhesion properties were correlated with the morphology, thickness and roughness of the polyaniline films, and the electrodeposition conditions (H3PO4 concentration and electrodeposition time) were optimized. The adhesion properties of this original polymer films were found to be similar to those of the best commercial glues. The conductivity of the polyaniline film was also demonstrated as well as the possibility for the polyaniline films to switch reversibly from a non-adhesive to an adhesive behavior. A wide range of applications, in the field of telecommunications, bioengineering, and more generally speaking MEMS (microelectromechanical systems) can be envisaged for these materials.