Improved manufacturing process for printed cantilevers by using water removable sacrificial substrate

• A cantilever beam fabricated by screen printing on flexible substrate is presented.
• The sacrificial layer is substituted by a sacrificial substrate whose thickness does not affect the manufacturing process.
• Both the sacrificial layer and the solvent are biodegradable.

Suspended structures are an important element in the vast majority of electromechanical systems. The definition of this kind of structures is a not totally resolved problem in printing electronics where the definition of a smooth sacrificial layer makes difficult their fabrication. Based on a previous work using a sacrificial substrate, we present in this paper a significant improvement of this technique in terms of reproducibility and yield rate. The sacrificial substrate is a commercial polyvinyl alcohol film which can be removed by water. The structural material is silver paste which has shown better performance during the removal of the sacrificial substrate than the previous approach based on an acetone bath. Furthermore, this sacrificial material is biodegradable as well as its solvent. In this paper, we show the fabrication process for printed cantilevers, including a characterization of their peak to peak displacements as a function of the applied acceleration and frequency. Moreover, the variation of the capacitance for different acceleration values is presented.