Molded printhead

Patent metadata

Field	Value
Publication number	US-10029467-B2
Application number	US-201314770608-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Feb 28, 2013
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

In one example, a printhead includes: a printhead die having a front face along which fluid may be dispensed from the die, the die molded into a monolithic molding having a channel therein through which fluid may pass directly to a back part of the die, the front face of the die exposed outside the molding and the back part of the die covered by the molding except at the channel; an electrical contact exposed outside the molding to connect to circuitry external to the printhead; a printed circuit board molded into the molding, the printed circuit board having an exposed front face co-planar with and surrounding the exposed front face of the die and a conductor electrically connected to the contact; and an electrical connection between the die and the printed circuit board conductor fully encapsulated in the molding.

First claim

What is claimed is:

1. A printhead, comprising:
a printhead die having a front face along which fluid may be dispensed from the die, the die molded into a monolithic molding having a channel therein through which fluid may pass directly to a back part of the die, the front face of the die exposed outside the molding and the back part of the die covered by the molding except at the channel;
an electrical contact exposed outside the molding to connect to circuitry external to the printhead;
a printed circuit board molded into the molding, the printed circuit board having an exposed front face co-planar with and surrounding the exposed front face of the die and a conductor electrically connected to the contact; and
an electrical connection between the die and the printed circuit board conductor.

2. The printhead of claim 1 , wherein the exposed front face of the die, the exposed front face of the printed circuit board, and a front face of the molding together form a continuous planar surface defining a front face of the printhead.

3. The printhead of claim 2 , wherein the electrical connection is between the back part of the die and the printed circuit board conductor and fully encapsulated in the molding.

4. The printhead of claim 3 , wherein:
the die includes a through-silicon-via from the back part of the die to circuitry internal to the die; and
the electrical connection comprises a wire bond fully encapsulated in the molding from the through-silicon-via to the printed circuit board conductor.

5. The printhead of claim 4 , wherein a back face of the molding opposite the front face forms a continuous planar surface except at the channel.

6. The printhead of claim 5 , wherein:
the printhead die comprises multiple printhead die slivers arranged parallel to one another laterally across the molding; and
the channel comprises multiple channels each through which fluid may pass directly to a back part of a corresponding one of the die slivers.

7. A method of fabricating the printhead of claim 1 , comprising:
placing multiple printhead dies face down on a carrier;
wire bonding each printhead die to the printed circuit board; and
overmolding the printhead dies and the printed circuit board on the carrier, including fully encapsulating the wire bonds, to produce the monolithic molding.

8. The method of claim 7 , wherein placing the printed circuit board on the carrier includes placing the printed circuit board on the carrier with each of multiple openings in the printed circuit board surrounding one or more of the printhead dies.

9. The method of claim 7 , further comprising placing a non-printhead die electronic device on the carrier and wire bonding the non-printhead die electronic device to the printed circuit board, and wherein the overmolding includes overmolding the non-printhead die electronic device on the carrier.

10. The method of claim 7 , further comprising:
separating the molded structure into individual print bars and then releasing the print bars from the carrier; or
releasing the molded structure from the carrier and then separating the molded structure into individual print bars.

11. A printhead, comprising:
multiple printhead dies embedded in a molding with fully encapsulated electrical conductors that extend from each of the dies to an exposed electrical contact, the dies and the molding together defining an exposed planar surface surrounding dispensing orifices at a front face of each of the dies, and the molding having a channel therein through which fluid may pass to the dies; and
a printed circuit board embedded in the molding, the conductors including first conductors in the printed circuit board connected to the contact, and second conductors connecting the first conductors to a back part of the dies, and the dies, the molding and the printed circuit board together forming the exposed planar surface surrounding the dispensing orifices at the front face of each of the dies.

12. The printhead of claim 11 , wherein the second conductors comprise bond wires.

13. The printhead of claim 12 , wherein:
each die includes a through-silicon-via from the back part of the die to circuitry internal to the die; and
each bond wire connects a through-silicon-via to a first conductor.

14. The printhead of claim 12 , further comprising a non-printhead die electronic device embedded in the molding and connected to a first conductor in the printed circuit board with bond wires fully encapsulated in the molding.

15. A printhead, comprising:
an elongated cuboidal printhead die sliver in a monolithic molding covering a back and sides of the die sliver leaving a front of the die sliver exposed along a planar surface that includes a front face of the die sliver and a front face of the molding surrounding the front face of the die sliver, the molding having an opening therein through which fluid may pass directly to a back part of the die sliver; and
a printed circuit board in the molding, the molding covering a back and sides of the printed circuit board leaving a front face of the printed circuit board exposed along the planar surface that includes the front face of the die sliver, the front face of the molding surrounding the front face of the die sliver, and the front face of the printed circuit board, the printed circuit board having conductors therein electrically connected to a back part of the die sliver covered by the molding.

16. The printhead of claim 15 , wherein:
the elongated cuboidal printhead die sliver comprises multiple elongated cuboidal die slivers arranged generally end to end along the molding in a staggered configuration in which one or more of the die slivers overlap an adjacent one or more of the die slivers; and
the opening comprises multiple openings each positioned at a back part of a corresponding one of the die slivers.

17. The printhead of claim 15 , wherein:
the elongated cuboidal printhead die sliver comprises multiple elongated cuboidal die slivers arranged parallel to one another laterally across the molding; and
the opening comprises multiple openings each positioned at a back part of a corresponding one of the die slivers.

Assignees

• Hewlett Packard Development Co

Inventors

• Choy Silam J
• Cumbie Michael W
• Mourey Devin Alexander
• Chen Chien-Hua

Classifications

• B41J2/1637 Primary

  molding · CPC title

• B41J2/14

  Structure thereof {only for on-demand ink jet heads} · CPC title

• B41J2/16

  Production of nozzles · CPC title

• B41J2002/14491

  Electrical connection · CPC title

• B41J2202/19

  Assembling head units · CPC title