Method of forming connection between electrode and actuator in an inkjet nozzle assembly

1. A method of forming an electrical connection between an electrode and an actuator in an inkjet nozzle assembly, said method comprising the steps of:

(a) providing a substrate having a layer of drive circuitry, said drive circuitry including the electrode for connection to the actuator, said actuator being a thermal bend actuator comprising a planar active beam member mechanically cooperating with a planar passive beam member;

(b) forming a wall of insulating material over said electrode;

(c) defining a via in at least said wall, said via revealing said electrode;

(d) filling said via with a conductive material using electroless plating to provide a connector post;

(e) depositing an active beam material onto a passive beam material such that said active beam material extends from said connector post in a plane perpendicular to said post thereby providing electrical connection between the actuator and the electrode;

(f) depositing a catalyst layer on a base of said via prior to said electroless plating; and,

(g) depositing a first metal pad over a top of said connector post prior to deposition of said active beam material, said first metal pad being configured to facilitate current flow from the connector post to the active beam member.

2. The method of claim 1 , wherein a distance between said actuator and said electrode is at least 5 microns.

3. The method of claim 1 , wherein said layer of drive circuitry is a CMOS layer of a silicon substrate.

4. The method of claim 1 , wherein said drive circuitry includes a pair of electrodes for each inkjet nozzle assembly, each of said electrodes being connected to said actuator with a respective connector post.

5. The method of claim 1 , wherein said wall of insulating material is comprised of silicon dioxide.

6. The method of claim 1 , wherein said via has sidewalls perpendicular to a face of said substrate.

7. The method of claim 1 , wherein said via has a minimum cross-sectional dimension of 1 micron or greater.

8. The method of claim 1 , wherein said conductive material is a metal.

9. The method of claim 1 , wherein said conductive material is copper.

10. The method of claim 1 , wherein said catalyst is palladium.

11. The method of claim 1 , wherein said conductive material is planarized by chemical mechanical planarization prior to forming said actuator.

12. The method of claim 1 , wherein said thermal bend actuator defines, at least partially, a roof of a nozzle chamber for said inkjet nozzle assembly.

13. The method of claim 12 , wherein said wall of insulating material defines a sidewall of said nozzle chamber.

14. The method of claim 1 , wherein said planar active beam member comprises a bent or serpentine beam element, said beam element having a first end positioned over a first connector post and a second end positioned over a second connector post, said first and second connector posts being adjacent each other.

15. The method of claim 14 , further comprising the step of:

depositing one or more second metal pads onto said passive beam material prior to deposition of said active beam material, said second metal pad being positioned to facilitate current flow in bend regions of said beam element.