Multilayered inductor

Abstract

A multilayer inductor 1 is fabricated, for example, by sandwiching a first magnetic material sheet (21) between a second magnetic material sheet (22) and a third magnetic material sheet (23) and integrating the three layers. The first magnetic material sheet (21) is preferably at least 0.2 mm thick and has a first spiral conductor pattern (31) having an extreme lead-out portion (310) formed on its upper major surface. The first sheet (21) is provided with a through-hole (4) extending between the opposed major surfaces and having a larger diameter on the conductor pattern bearing surface. The through-hole (4) is filled with a conductor (35) contiguous to the first conductor pattern (31). The second magnetic material sheet (22) has a second spiral conductor pattern (32) having an extreme lead-out portion (320) formed on its upper major surface and connected to the conductor (35) in the through-hole (4). The magnetic material sheets (21, 22) on their major surfaces having the first and second conductor patterns (31, 32) formed thereon are provided with dummy conductor patterns (61, 65) which are spaced from and opposed to the extreme lead-out portions (310, 320), respectively, and external electrodes are connected. Benefits include easy fabrication, safe connection, least property variation, improved manufacturing yield and reliability.

Dependencies are inferred from the claim text.