All inkjet printed piezoelectric polymer actuators for microfluidic lab on a chip systems Printing technologies for the fabrication of electronic components have emerged in recent years and have attracted interest due to their capabilities of cost effective material deposition and their suitability for large area coatings. In this thesis the benefits of inkjet printing technologies are used to manufacture piezoelectric actuators that are suitable for integration in polymer based disposable microfluidic lab on a chip (LOC) systems. Based on analytical models of actuator behavior piezoelectric actuators with poly(vinylidene fluoride co trifluoroethylene) (P(VDF TrFE)) as the active material are inkjet printed and characterized in detail for the first time here. The thermal treatment applied to the P(VDF TrFE) films exhibits a significant influence on device performance and morphology. Annealing at temperatures between 110 and 140 °C yields distinct piezoelectric behavior. These findings are employed to demonstrate the function of a membrane pump with an inkjet printed actuator with pump rates up to 130 µL min which is suitable for applications in LOC systems. Compared to the state of the art the manufacturing approach introduced here as well as the established knowledge about the behavior of inkjet printed P(VDF TrFE) actuators are novel. The low processing temperatures and the use of digital printing technologies lead to cost effective processing compared to conventional lithography and vacuum based manufacturing approaches. Different from most current micropumps an additional assembly step is not required which would be necessary when an actuator is manufactured separately and then attached to the pump membrane. Furthermore the manufacturing approach and design introduced here are compatible with processes and materials that are used in LOC systems. They allow a cost effective integration of further functionalities leading to a higher degree of integration and thus smarter systems.