Method of manufacturing an inkjet print head and an inkjet print head with induced crystal phase change actuation

An inkjet print head having at least one ejection unit for ejection of a droplet of a liquid, the ejection unit comprising:

• a pressure chamber for holding an amount of the liquid;
• an actuator forming a flexible wall of the pressure chamber and arranged for changing a volume of the pressure chamber upon receipt of an actuation signal;
• and
• a nozzle orifice in liquid communication with the pressure chamber for expelling the droplet of the liquid upon a suitable change of the volume of the pressure chamber,
• wherein the actuator comprises:
• a base layer arranged over the pressure chamber;
• and
• an actuator stack arranged on the base layer,
• wherein the actuator stack comprises a piezoelectric material having a predetermined misfit strain such that, at an operating temperature, the operating temperature being a temperature at which the inkjet print head is operated for expelling droplets of a liquid, the piezoelectric material has a predetermined first crystal phase and, upon application of the actuation signal, has a second crystal phase, different from the first crystal phase,
• wherein the predetermined misfit strain is selected based on a misfit strain-electric field crystal phase relation for at least one composition of the piezoelectric material such that, with a predetermined change in electric field, a crystal phase change in the piezoelectric material is induced.