ACTUATOR

An electrostatic actuator (42) for ejecting fluid from a plurality of chambers, comprising a plurality of conductors (44,74) arranged on a bonding surface of a substrate, wherein each of the conductors (44,74) has an associated chamber (36); a plurality of blockers (104) arranged on the bonding surface of the substrate and positioned between each of the conductors (44,74). The electrostatic actuator also comprises a conductive layer (90) comprising a flexible conductive membrane (86) forming at least part of a wall of each chamber (36); and a plurality of bumps (102); and a voltage source (60) operably connected to each of the conductors (44,74) and the conductive layer (90), for selectively applying a voltage between each of the conductors (44,74) and the conductive layer (90). Each of the plurality of bumps (102) is located over a corresponding one of the plurality of blockers (104) across a gap (58).