Manufacturing process for piezoelectric strain sensor sheet involving transfer printing methods

In this paper, we present a novel sensor sheet manufacturing process that involves transfer printing methods using adhesive rubber stamps. By using these methods, not only ultrathin microsensors but also microcontroller and amplifier chips required for the fabrication of sensor devices can be mounted. We successfully transfer-printed a very fragile 5-mm-long, 1-mm-wide, 5-µm-thick high-aspect-ratio ultrathin strain sensor onto a flexible printed-circuit substrate. Then, we connected the sensor to the wiring by printing a conductive paste using a screen printer. A large ferroelectric polarization-voltage hysteresis curve was obtained even after the transfer printing process. Since an output voltage corresponding to the magnitude of the strain from the developed sensor was generated, it was confirmed that ultrathin sensors could be transfer-printed to the flexible substrate by this transfer technique without damage.