Printed circuit board fluid ejection apparatus

Patent metadata

Field	Value
Publication number	US-2018201017-A1
Application number	US-201815918411-A
Country	US
Kind code	A1
Filing date	Mar 12, 2018
Priority date	Jan 30, 2014
Publication date	Jul 19, 2018
Grant date	—

Abstract

In an example, a fluid ejection apparatus includes a printed circuit board including a conductor layer, a cover layer forming a surface of the printed circuit board, and a cavity. A printhead die may be embedded in a molding material in the cavity.

First claim

What is claimed is:

1 . A fluid ejection apparatus comprising:
a printed circuit board including a conductor layer, a cover layer forming a surface of the printed circuit board; and a plurality of printhead die electrically connected to the conductor layer and embedded in a molding material, each printhead die disposed in a cavity in the printed circuit board; wherein the plurality of fluid ejection dies are arranged in a staggered, end-to-end pattern along a width of the printed circuit board.

2 . The apparatus of claim 1 , wherein each printhead die includes a through-silicon via extending to a bottom surface to electrically connect that printhead die to the conductor layer.

3 . The apparatus of claim 1 , wherein the cover layer comprises a polymer.

4 . The apparatus of claim 3 , wherein the cover layer comprises polyimide, polyethylene naphthalate, or polyethylene terephthalate.

5 . The apparatus of claim 1 , wherein the cover layer is coupled to the conductor layer by an adhesive.

6 . The apparatus of claim 1 , wherein the cover layer comprises a polyimide film and an epoxy adhesive between the polyimide film and the conductor layer.

7 . The apparatus of claim 1 , wherein the cover layer is a first cover layer forming a first surface of the printed circuit board and wherein the printed circuit board includes a second cover layer forming a second surface, opposite the first surface, of the printed circuit board.

8 . The apparatus of claim 1 , wherein the printhead die comprises an arrangement of printhead die slivers each disposed in a corresponding cavity in the printed circuit board.

9 . The apparatus of claim 1 , wherein each printhead die comprises multiple die slivers.

10 . The apparatus of claim 1 , further comprising a fluid feed channel extending through a surface of the printed circuit board to deliver fluid to the plurality of printhead die.

11 . The apparatus of claim 1 , wherein the molding material embedding each printhead die is level with the cover layer

12 . A fluid ejection apparatus comprising:
a plurality of printhead dies; a printed circuit board having a conductor layer and a cavity in which the plurality of printhead dies are disposed, the printhead dies being embedded in a molding material in the cavity; and a cover layer forming a surface of the printed circuit board and having an opening exposing a bond pad of the conductor layer, and wherein each of the plurality of printhead dies is electrically connected to the bond pad; wherein the plurality of printhead dies are arranged end-to-end in two rows across the printed circuit board, and wherein placement of the printhead dies is staggered such that ends of the printhead dies overlap laterally between the two rows.

13 . The fluid ejection apparatus of claim 12 , wherein each of the plurality of printhead dies is electrically connected to the bond pad of the printed circuit board by a wire bond.

14 . The fluid ejection apparatus of claim 13 , wherein the fluid ejection apparatus further comprises an encapsulant material encapsulating the wire bond.

15 . The apparatus of claim 11 , wherein the molding material is level with the cover layer.

16 . The apparatus of claim 11 , wherein each printhead die includes a through-silicon via extending to a bottom surface of that die to electrically connect that printhead die to the conductor layer.

17 . The apparatus of claim 11 , wherein:
the plurality of printhead dies is a first plurality of printhead dies; the printed circuit board comprises an elongated printed circuit board; and the apparatus includes a second plurality of printhead dies embedded in a molding material in another cavity of the printed circuit board.

18 . A method for making a fluid ejection apparatus, comprising:
providing a printed circuit board including a conductor layer, a cover layer forming a surface of the printed circuit board, wherein the cover layer includes an opening exposing a bond pad of the conductor layer, and a cavity; embedding a plurality of printhead die in a molding material in the cavity, wherein the plurality of printhead dies are arranged end-to-end in two rows across the printed circuit board, and placement of the printhead dies is staggered such that ends of the printhead dies overlap laterally between the two rows, and wherein the molding material is level with the cover layer; and electrically connecting the printhead die to the bond pad of the conductor layer.

19 . The method of claim 18 , further comprising, prior to said embedding the printhead die, forming the cover layer over the conductor layer, and forming the cavity in the printed circuit board through the cover layer after said forming the cover layer over the conductor layer.

20 . The method of claim 18 , further comprising, prior to said embedding the printhead die, forming the cover layer over the conductor layer, the cover layer including an opening corresponding to the cavity prior to said forming.

Assignees

• Hewlett Packard Development Co

Inventors

• Lutnesky Gary G
• Choy Silam J

Classifications

• B41J2202/11

  characterised by specific geometrical characteristics · CPC title

• B41J2/162

  Manufacturing of the nozzle plates · CPC title

• B41J2/14072

  Electrical connections, e.g. details on electrodes, connecting the chip to the outside... · CPC title

• B41J2202/19

  Assembling head units · CPC title

• B41J2/1603

  of the front shooter type · CPC title