Inkjet nozzle assembly with actuatable nozzle chamber

1. A nozzle assembly for an inkjet printhead, the nozzle assembly comprising:

a substrate assembly defining an ink inlet aperture;

a nozzle comprising a wall portion extending from the substrate assembly to bound the ink inlet aperture, and a moveable crown portion from which a skirt portion depends, the wall portion and the skirt portion defining a peripheral wall of a nozzle chamber;

an anchor extending from the substrate assembly; and

a thermal bend actuator connected between the anchor and a lever arm, which lever arm is in turn connected to the nozzle, the thermal bend actuator, upon actuation, moving the crown and skirt portions relative to the wall portion to eject ink in the nozzle chamber out through the nozzle opening, wherein

the skirt portion and the wall portion are separated by a gap, and the wall portion is shaped with an inwardly directed lip in the vicinity of the gap, the inwardly directed lip facilitating the formation of a fluidic seal effected via surface tension across the gap.

2. A nozzle assembly as claimed in claim 1 , wherein the actuator has spaced active and passive beams.

3. A nozzle assembly as claimed in claim 2 , wherein at least a portion of both beams are of a conductive ceramic material.

4. A nozzle assembly as claimed in claim 3 , wherein the passive beam is between the active beam and the substrate assembly.

5. A nozzle assembly as claimed in claim 1 , wherein the anchor is mounted on conductive pads which form an electrical connection with the actuator.

6. A nozzle assembly as claimed in claim 1 , wherein the substrate assembly has:

a silicon substrate;

a dielectric layer deposited on the silicon substrate; and

a CMOS passivation layer deposited on the dielectric layer.

7. A nozzle assembly as claimed in claim 6 , wherein said anchor is mounted to the CMOS passivation layer.