Integrated actuators based on PZT thick films for microsystems applications

Piezoceramic thick films based on lead zirconate titanate (PZT) offer the possibility of integrated actuator structures for microsystems applications. By use of the screen printing technology, thick film actuators can be directly prepared on the substrate with high accuracy and reproducibility. Compared to conventional assembling techniques PZT thick films show strong bonding to the substrate and high interface reliability under operation. The authors developed a screen printable PZT thick film paste which shows excellent dielectric and electromechanical properties like dielectric constant value of epsilon(ind33)T/epsilon(ind0) = 1900 and piezoelectric coefficient of d(ind33) = 210 pC/N after sintering. It has been used for actuator, sensor and ultrasonic transducer applications so far. The paper will report in detail on PZT thick film actuators for adaptive optics.