# US 7,408,120 B2 · Printed circuit board having axially parallel via holes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,408,120 B2 - Document ID: US7408120B2 - Status: Granted - Kind: B2 - Application number: 11/042,360 - Filed: 2005-01-24 - Published: 2005-08-18 - Granted: 2008-08-05 - Earliest claimed: 2004-02-13 - Assignees: Samsung Electro-Mechanics Co., Ltd. - Inventors: Young Woo Kim; Byoung Youl Min; Chang Myung Ryu; Han Kim - Web page: https://patentgrep.com/patent/US7408120B2 ## CPC - H05K 1/115: {Via connections; Lands around holes or via connections (H05K1/112 takes precedence)} - H05K 3/429: {Plated through-holes specially for multilayer circuits, e.g. having connections to inner circuit layers} - H05K 3/4602: {characterized by a special circuit board as base or central core whereon additional circuit layers are built or additional circuit boards are laminated} - H05K 2201/09536: Buried plated through-holes, i.e. plated through-holes formed in a core before lamination - H05K 2201/096: Vertically aligned vias, holes or stacked vias - H05K 2201/09809: Coaxial layout - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract Disclosed is a PCB having axially parallel via holes, in which an outer ground via hole, acting as a ground, is formed around a via hole for intercircuit connection in the PCB, thereby minimizing the effect of noise caused by the via hole. ## Claims ### Claim 1 A printed circuit board having axially parallel via holes, comprising: a plurality of circuit layers, on which circuit patterns are formed; a plurality of insulating layers interposed between the plurality of circuit layers, thereby forming internal and external circuit layers; a plurality of via holes having a continuous curvilinear section, which extends perpendicular to a surface of any one of the plurality of circuit layers and which is plated with a first conductive material on walls thereof; an outer ground via hole having a continuous curvilinear section surrounding at least two via holes of the plurality of via holes, which extends transverse to and for a distance equal to the thickness of at least three insulating layers having internal circuit layers disposed therebetween, the outer ground via hole extending in an axial direction of the via hole surrounded thereby while being separated from a wall of the via hole by a predetermined distance and which is plated with a second conductive material on the wall thereof; an insulating material packed between the via hole, which is surrounded by the outer ground via hole, and the outer ground via hole; and wherein the via hole, which is surrounded by the outer ground via hole, is selected from the group consisting of: an inner via hole electrically connecting at least two internal circuit layers; a staggered via hole having a step-shaped path and electrically connecting at least two circuit layers; a stacked via hole having an straight-shaped path and electrically connecting at least two circuit layers; a through via hole electrically connecting the external circuit layers; and a blind via hole electrically connecting at least two circuit layers, wherein the blind via hole does not pass completely through the printed circuit board. ### Claim 2 (depends on 1) The printed circuit board as set forth in claim 1, wherein the outer ground via hole is grounded. ### Claim 3 (depends on 1) The printed circuit board as set forth in claim 1, wherein the second conductive material of the outer ground via hole is a copper plating layer. ### Claim 4 (depends on 1) The printed circuit board as set forth in claim 1, wherein the via hole, which is surrounded by the outer ground via hole, is coaxial to the outer ground via hole. ### Claim 5 (depends on 1) The printed circuit board as set forth in claim 1, wherein the via hole, which is surrounded by the outer ground via hole, is axially parallel to the outer ground via hole. ### Claim 6 A printed circuit board having axially parallel via holes, comprising: a plurality of circuit layers, on which circuit patterns are formed; a plurality of insulating layers interposed between the plurality of circuit layers, thereby forming internal and external circuit layers; a plurality of via holes having a continuous curvilinear section, which extends perpendicular to a surface of any one of the plurality of circuit layers and which is plated with a first conductive material on walls thereof; an outer ground via hole having a continuous curvilinear section surrounding at least two via holes of the plurality of via holes, which extends transverse to and for a distance equal to the thickness of at least three insulating layers having internal circuit layers disposed therebetween, the outer ground via hole extending in an axial direction of the via hole surrounded thereby while being separated from a wall of the via hole by a predetermined distance and which is plated with a second conductive material on the wall thereof; an insulating material packed between the via hole, which is surrounded by the outer ground via hole, and the outer ground via hole; and wherein the via hole, which is surrounded by the outer ground via hole, is selected from the group consisting of: an inner via hole electrically connecting at least two internal circuit layers; a staggered via hole having a step-shaped path and electrically connecting at least two circuit layers; a stacked via hole having an straight-shaped path and electrically connecting at least one internal and at least one external circuit layers; a blind via hole electrically connecting at least two circuit layers, wherein the blind via hole does not pass completely through the printed circuit board. ### Claim 7 A printed circuit board having axially parallel via holes, comprising: a plurality of circuit layers, on which circuit patterns are formed; a plurality of insulating layers interposed between the plurality of circuit layers, thereby forming internal and external circuit layers; a plurality of via holes having a continuous curvilinear section, which extends perpendicular to a surface of any one of the plurality of circuit layers and which is plated with a first conductive material on walls thereof; an outer ground via hole surrounding at least one via hole of the plurality of via holes, which extends transverse to and for a distance equal to the thickness of at least three insulating layers having internal circuit layers disposed therebetween, the outer ground via hole extending in an axial direction of the via hole surrounded thereby while being separated from a wall of the via hole by a predetermined distance and which is plated with a second conductive material on the wall thereof; and an insulating material packed between the via hole, which is surrounded by the outer ground via hole, and the outer ground via hole.