Patent ID: 8450902

Claim:
An electrostatic actuator operable to eject fluid from a fluid ejector for ink let recording or printing device, the electrostatic actuator comprising: a substrate; an electrode having a flat surface portion and a device layer having a flat conductive surface portion formed on the substrate; and a deflectable conductive membrane having discontinuous surface positioned in proximity to the flat surface portion of the electrode and the flat surface portion of the device layer so as to provide a gap between the electrode and the deflectable membrane and between the device layer and the deflectable membrane, the deflectable membrane being anchored on the substrate via at least two anchors and having a conductive landing post about midway between the at least two anchors that contacts the flat conductive surface portion of the device layer when the deflectable membrane is fully deflected, wherein the gap comprises at least one first region having a first gap height positioned near the one or more anchors and at least one second region having a second gap height positioned farther from the anchors than the first region, the first gap height being smaller than the second gap height, the first gap height and the second gap height being provided by the discontinuous surface of the deflectable membrane, with the flat surface portion of the electrode extending from a first location of the first gap to a second location of the second gap, wherein the first gap height, the second gap height, or both are sized to reduce a voltage required to cause the conductive landing post of the deflectable conductive membrane to make contact with the device layer, wherein the size of the gap in the first region ranges from about 0.1 um to about 3.0 um, and the size of the gap in the second region ranges from about 0.125 to about 4.0 um, wherein the deflectable conductive membrane is arranged to be substantially planar when not deflected and wherein the electrostatic actuator is operable to eject fluid from a fluid ejector for ink jet recording or printing device.