# US 10,500,858 B2 · Printed circuit board fluid ejection apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,500,858 B2 - Document ID: US10500858B2 - Status: Granted - Kind: B2 - Application number: 15/918,411 - Filed: 2018-03-12 - Published: 2018-07-19 - Granted: 2019-12-10 - Earliest claimed: 2018-03-12 - Assignees: Hewlett-Packard Development Company, L.P. - Applicants: Hewlett-Packard Development Company, L.P. - Inventors: Gary G. Lutnesky; Silam J. Choy - Web page: https://patentgrep.com/patent/US10500858B2 ## CPC - B41J 2/1433: {Structure of nozzle plates} - B41J 2/14072: {Electrical connections, e.g. details on electrodes, connecting the chip to the outside...} - B41J 2/155: for line printing - B41J 2/1603: {of the front shooter type} - B41J 2/162: {Manufacturing of the nozzle plates} - B41J 2/1623: {bonding and adhesion} - B41J 2/1637: {molding} - B41J 2/16535: {using wiping constructions (B41J2/16552 takes precedence)} - B41J 2002/14491: {Electrical connection} - B41J 2202/11: characterised by specific geometrical characteristics - B41J 2202/19: Assembling head units - B41J 2202/20: Modules - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## 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. ## Claims ### Claim 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 printhead die electrically connected to the conductor layer and embedded in a molding material, the printhead die disposed in a cavity in the printed circuit board; wherein the printhead die includes a through-silicon via extending to a bottom surface to electrically connect the printhead die to the conductor layer; wherein the molding material embedding the printhead die is level with the cover layer. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the printhead die comprises a plurality of printhead dies arranged in a staggered, end-to-end pattern along a width of the printed circuit board. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the cover layer comprises a polymer. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the cover layer comprises polyimide, polyethylene naphthalate, or polyethylene terephthalate. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the cover layer is coupled to the conductor layer by an adhesive. ### Claim 6 (depends on 1) 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. ### Claim 7 (depends on 1) 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. ### Claim 8 (depends on 1) 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. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the printhead die comprises multiple die slivers. ### Claim 10 (depends on 1) 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 printhead die. ### Claim 11 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. ### Claim 12 (depends on 11) The fluid ejection apparatus of claim 11, wherein each of the plurality of printhead dies is electrically connected to the bond pad of the printed circuit board by a wire bond. ### Claim 13 (depends on 12) The fluid ejection apparatus of claim 12, wherein the fluid ejection apparatus further comprises an encapsulant material encapsulating the wire bond. ### Claim 14 (depends on 11) The fluid ejection apparatus of claim 11, wherein the molding material is level with the cover layer. ### Claim 15 (depends on 11) The fluid ejection 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. ### Claim 16 (depends on 11) The fluid ejection 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. ### Claim 17 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 dies 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 dies to the bond pad of the conductor layer. ### Claim 18 (depends on 17) The method of claim 17, further comprising, prior to said embedding the plurality of printhead dies, 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. ### Claim 19 (depends on 17) The method of claim 17, further comprising, prior to said embedding the printhead dies, forming the cover layer over the conductor layer, the cover layer including an opening corresponding to the cavity prior to said forming.