# US 9,049,793 B2 · Multi-piece-array and method of manufacturing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,049,793 B2 - Document ID: US9049793B2 - Status: Granted - Kind: B2 - Application number: 13/876,670 - Filed: 2011-09-30 - Published: 2013-07-18 - Granted: 2015-06-02 - Earliest claimed: 2010-10-08 - Assignees: Ngk Spark Plug Co., Ltd. - Applicants: Yoshitaka Yoshida; Hiroaki Yamamoto - Inventors: Yoshitaka Yoshida; Hiroaki Yamamoto - Web page: https://patentgrep.com/patent/US9049793B2 ## CPC - H05K 1/0306: {Inorganic insulating substrates, e.g. ceramic, glass} - B32B 3/30: characterised by a layer formed with recesses or projections, e.g. {hollows, grooves, protuberances, ribs (apertured layer B32B3/266; layer with cavities or internal voids B32B3/26)} - H05K 3/00: Apparatus or processes for manufacturing printed circuits - H05K 3/0052: {Depaneling, i.e. dividing a panel into circuit boards; Working of the edges of circuit boards} - H05K 1/09: Use of materials for the {conductive, e.g. } metallic pattern - H05K 3/0097: {Processing two or more printed circuits simultaneously, e.g. made from a common substrate, or temporarily stacked circuit boards (H05K3/0052 takes precedence)} - H05K 2201/09036: Recesses or grooves in insulating substrate - H05K 2201/0909: Preformed cutting or breaking line - H05K 2201/09154: Bevelled, chamferred or tapered edge - H05K 2201/09863: Concave hole or via - Y10T 156/10: Methods of surface bonding and/or assembly therefor - Y10T 428/15: Sheet, web, or layer weakened to permit separation through thickness - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A multi-piece-array formed by laminating a plurality of ceramic layers includes: a product region where a plurality of wiring board portions having a rectangular shape in plan view and including cavities are arranged in matrix; a redundant portion that is positioned along a periphery of the product region; and dividing grooves that are formed on a front surface and/or a back surface along a boundary between the wiring board portions and a boundary between the wiring board portion and the redundant portion. A deepest portion of the dividing groove has an arc shape and the dividing groove includes a middle portion, and a width of the deepest portion is greater than a width of the groove inlet and a width of the middle portion is equal to or less than the width of the groove inlet. ## Claims ### Claim 1 A multi-piece-array that is formed by laminating a plurality of ceramic layers and has a front surface and a back surface, the multi-piece-array comprising: a product region where a plurality of wiring board portions having a rectangular shape in plan view and including cavities are arranged in matrix; an edge portion that is positioned along a periphery of the product region; and dividing grooves that are formed on at least one of the front surface and the back surface along a boundary between the wiring board portions and a boundary between the wiring board portion and the edge portion, wherein a deepest portion of the dividing groove has an arc shape and the dividing groove includes a middle portion between the deepest portion and a groove inlet on a cross-section orthogonal to an extending direction of the dividing groove, and wherein a width of the deepest portion is greater than a width of the groove inlet and a width of the middle portion is equal to or less than the width of the groove inlet. ### Claim 2 (depends on 1) The multi-piece-array according to claim 1, wherein a radius of the arc shape of the deepest portion of the dividing groove is 6 μm or more. ### Claim 3 (depends on 1) The multi-piece-array according to claim 1, wherein the ceramic layer is made of alumina, mullite, glass-ceramic, or aluminum nitride. ### Claim 4 (depends on 1) A method of manufacturing the multi-piece-array of claim 1, the method comprising: forming a green sheet laminate body by laminating and press-bonding a plurality of green sheets, a conductor layer being formed on at least one of a front surface and a back surface of the green sheet laminate body and cavities opened to the front surface of the uppermost layer of the green sheet laminate body being formed at the green sheet laminate; irradiating and scanning the green sheet laminate body multiple times with a laser of which a focal point is adjusted to the vicinity of the front surface or the back surface of the green sheet laminate body to form the dividing grooves on at least one of the front surface and the back surface of the green sheet laminate body along the boundary between the plurality of wiring board portions, which are arranged in matrix, and the boundary between the wiring board portion and the edge portion; and firing the green sheet laminate body on which the dividing grooves are formed. ### Claim 5 (depends on 4) The method according to claim 4, wherein the front surface and the back surface of the green sheet laminate body are irradiated and scanned multiple times with the laser, respectively. ### Claim 6 (depends on 4) The method according to claim 4, wherein the laser used in the forming of the dividing grooves is a YAG laser, a carbon dioxide laser, an excimer laser, a YVO4 laser, a semiconductor laser, or ruby laser. ### Claim 7 (depends on 4) The method according to claim 4, wherein a deepest portion of the dividing groove has an arc shape and the dividing groove includes a middle portion between the deepest portion and a groove inlet on a cross-section orthogonal to an extending direction of the dividing groove, and a width of the deepest portion is greater than a width of the groove inlet and a width of the middle portion is equal to or less than the width of the groove inlet. ### Claim 8 (depends on 4) The method according to claim 4, wherein a radius of the arc shape of the deepest portion of the dividing groove is 6 μm or more.