Development of high voltage photovoltaic micro-devices for driving micro actuators

Photovoltaic devices capable of generating more than 200 volts with an area of 1 cm(2) have been developed for directly driving microactuators such as piezoelectric or electrostatic actuators. The micro-devices interconnect 285 micro cells (unit cell size: about 0.5 mm x 2.0 mm) in series, and have an open circuit voltage (V-oc) of 207 volts, a short circuit current (I-sc) of 36.6 mu A, a maximum output power (P-max) of 4.65 mW and a fill factor (F.F.) of 0.615 under AM (Air Mass) 1.5 and 100 mW/cm(2) illumination. This voltage is the highest in the world for the area of 1 cm(2). The series connection is precisely processed by a focused laser beam, thereby significantly reducing the area needed for device connections. It has been confirmed that a piezoelectric polymer can be directly driven by the electrical output in evaluating the potential of the devices to be used as a microactuator's power source.