Murata Manufacturing Co., Ltd.

Mitsuru Ueda

Hiroki Hashimoto

Tatsuya Mizuno

Masaharu Konoue

Yukio Maeda

Tomoyuki Maeda

A highly reliable multilayer coil component is provided without forming voids between magnetic ceramic layers and internal conductor layers. According to the multilayer coil component, an internal stress problem is reduced, the direct current resistance is low, and fracture of internal conductors caused by the surge or the like is not likely to occur. An acidic solution is allowed to permeate a magnetic ceramic element from a side surface thereof through a side gap portion which is a region between side portions of the internal conductors and the side surface of the magnetic ceramic element and to reach interfaces between the internal conductors and a magnetic ceramic located therearound. A pore area ratio of the magnetic ceramic of the side gap portion which is located between the side portions of the internal conductors and the side surface of the magnetic ceramic element is set in the range of 6% to 28%.

Multilayer coil component and method for manufacturing the same

A method for manufacturing a ceramic electronic component capable of preventing degradation of the self alignment property and product characteristics due to absorption of flux into pores of a ceramic element assembly during soldering in mounting and a ceramic electronic component. In the method, a ceramic element assembly is subjected to an oil-repellent treatment by using an oil-repellent agent containing a polyfluoropolyether compound as a primary component and hydrofluoroether as a solvent, so as to avoid absorption of the flux by the ceramic element assembly.

Method for manufacturing ceramic electronic component

A multilayer coil component includes internal conductors made of silver (Ag) having metal films provided on surfaces thereof to suppress migration of Ag contained in the internal conductors and/or relieve internal stress between magnetic ceramic layers and internal conductor layers without forming gaps at interfaces between the internal conductors including the metal films and a magnetic ceramic surrounding the internal conductors and the interfaces between the internal conductors and the magnetic ceramic. In a manufacturing method for forming a multilayer coil, an acidic solution containing a metal is allowed to penetrate a magnetic ceramic through side surfaces thereof and side gap sections that are regions between side portions of internal conductors and the side surfaces to reach the interfaces between the internal conductors and a surrounding magnetic ceramic, whereby the metal is deposited on surfaces of the internal conductors.

Ceramic electronic component

A multilayer coil component is provided in which solder fusibility and a self-alignment property are prevented from being degraded due to absorption of a flux in a soldering step. The multilayer coil component has no voids present at interfaces between internal conductorsand a magnetic ceramiclocated therearound. A magnetic ceramic forming a central regionhas a region (side gap portion) which extends from a side surfaceof the magnetic ceramic element to the internal conductors and which has a pore area ratio of 6% to 20%. At least one of a first external layer region, located at an upper side of the central region, and a second external layer region, located at a lower side of the central region (an external layer region at a mounting surface side of a mounting substrate), has a pore area ratio of less than 5%.

Multilayer coil component

A multilayer coil component is constructed such that inductance can be finely adjusted and the coupling between two helical coils can be strengthened without increasing the types of patterns of coil conductors. Coil conductors of a first coil unit are connected to each other in series via via-hole conductors so as to form a first helical coil. Coil conductors of a second coil unit are connected to each other in series via via-hole conductors so as to form a second helical coil. The first and second helical coils are coaxially positioned, have different numbers of turns, and are electrically connected to each other in parallel. The sum of turns of the coil conductors facing each other at a portion where the first coil unit and the second coil unit are adjacent to each other is larger than the sum of turns of the coil conductors positioned on both outer sides in the coil axis direction of the first and second helical coils.

Growing community of inventors

Shiga-ken, Japan

Mitsuru Ueda