# US 7,607,216 B2 · Method for manufacturing monolithic ceramic electronic component > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,607,216 B2 - Document ID: US7607216B2 - Status: Granted - Kind: B2 - Application number: 11/735,577 - Filed: 2007-04-16 - Published: 2007-08-09 - Granted: 2009-10-27 - Earliest claimed: 2004-10-18 - Assignees: Murata Manufacturing Co., Ltd. - Inventors: Ryuichiro Wada; Tetsuya Ikeda - Web page: https://patentgrep.com/patent/US7607216B2 ## CPC - H01F 41/046: {structurally combined with ferromagnetic material} - H01F 17/0013: {with stacked layers} - H05K 1/165: {incorporating printed inductors} - H05K 1/0306: {Inorganic insulating substrates, e.g. ceramic, glass} - H05K 3/4611: {by laminating two or more circuit boards (H05K3/4652 takes precedence)} - H05K 3/4629: {laminating inorganic sheets comprising printed circuits, e.g. green ceramic sheets} - H05K 2201/086: for inductive purposes, e.g. printed inductor with ferrite core - H05K 2201/09763: Printed component having superposed conductors, but integrated in one circuit layer - H05K 2203/308: Sacrificial means, e.g. for temporarily filling a space for making a via or a cavity or for making rigid-flexible PCBs - Y10T 29/4902: Electromagnet, transformer or inductor - Y10T 29/49069: Data storage inductor or core - Y10T 29/49071: by winding or coiling - Y10T 29/49073: by assembling coil and core - Y10T 29/49144: by metal fusion - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A multilayer composite including a core made of a magnetic ceramic sintered compact disposed therein, and shrinkage restraining layers including an inorganic powder that is not substantially sintered at the sintering temperature of the green ceramic layers are sintered in order to reduce the difference in shrinkage behavior during firing between the core and the green ceramic layers. ## Claims ### Claim 1 A method for manufacturing a monolithic ceramic electronic component including an inductor element, the method comprising: a step of forming a multilayer composite that includes a core made of a magnetic ceramic sintered compact, a coil conductor formed around the core, at least two green ceramic layers laminated such that the core and the coil conductor are sandwiched therebetween, and a shrinkage restraining layer arranged in contact with at least one of the green ceramic layers and including an inorganic material powder that is not substantially sintered at a sintering temperature of the green ceramic layers; and the step of firing the multilayer composite at the sintering temperature of the green ceramic layers. ### Claim 2 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the step of forming the multilayer composite includes: a step of preparing the core; a step of preparing a plurality of ceramic green sheets for the green ceramic layers; a step of forming a first conductor pattern for a portion of the coil conductor on a first main surface of a first one of the ceramic green sheets; a step of forming a second conductor pattern for another portion of the coil conductor on a first main surface of a second one of the ceramic green sheets; and a step of stacking the first ceramic green sheet and the second ceramic green sheet such that the first main surface of the first ceramic green sheet opposes the first main surface of the second ceramic green sheet with the core therebetween, and such that ends of the first conductor pattern are in contact with ends of the second conductor pattern to define a conductor having a coil shape. ### Claim 3 (depends on 2) The method for manufacturing the monolithic ceramic electronic component according to claim 2, wherein the step of stacking the first ceramic green sheet and the second ceramic green sheet includes: a step of disposing the core on the first main surface of the first ceramic green sheet such that the ends of the first conductor pattern protrude from the core; and a step of stacking the second ceramic green sheet on the first ceramic green sheet with the core therebetween. ### Claim 4 (depends on 2) The method for manufacturing the monolithic ceramic electronic component according to claim 2, wherein the step of forming the multilayer composite further includes a step of forming the shrinkage restraining layer on a second main surface opposite the first main surface of the first ceramic green sheet and a second main surface opposite the first main surface of the second ceramic green sheet. ### Claim 5 (depends on 2) The method for manufacturing the monolithic ceramic electronic component according to claim 2, wherein each of the first and second conductor patterns includes a plurality of conductive strips, such that the coil conductor includes a plurality of turns. ### Claim 6 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the core is one of a flat plate, a substantially circular cylinder, a substantially elliptical cylinder, and a ring. ### Claim 7 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the shrinkage restraining layer is arranged so as to define an outermost layer of the multilayer composite, and the method further includes a step of removing the shrinkage restraining layer after the step of firing. ### Claim 8 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the shrinkage restraining layer is disposed at a specific interface of the green ceramic layers, and the shrinkage restraining layer is solidified by permeation of a portion of constituents of the green ceramic layers in the step of firing. ### Claim 9 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the multilayer composite further includes first shield plates made of a magnetic ceramic sintered compact disposed along specific interfaces of the green ceramic layers such that the core and the coil conductor are disposed between the first shield plates in the stacking direction. ### Claim 10 (depends on 9) The method for manufacturing the monolithic ceramic electronic component according to claim 9, wherein the multilayer composite further includes second shield plates made of a magnetic ceramic sintered compact and arranged such that the core and the coil conductor are sandwiched therebetween, at the interface of the green ceramic layers in which the core and the coil conductor are disposed. ### Claim 11 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the monolithic ceramic electronic component is a single-function element having a function of an inductor. ### Claim 12 (depends on 11) The method for manufacturing the monolithic ceramic electronic component according to claim 11, wherein the green ceramic layers primarily include one of a low-temperature co-fired ceramic material and a magnetic material. ### Claim 13 (depends on 1) The method for manufacturing the monolithic ceramic electronic component according to claim 1, wherein the monolithic ceramic electronic component is a multilayer ceramic substrate having a plurality of functions including a function of an inductor. ### Claim 14 (depends on 13) The method for manufacturing the monolithic ceramic electronic component according to claim 13, wherein the green ceramic layers primarily include a low-temperature co-fired ceramic material.