US 12,464,642 B2
Wiring circuit board and method of producing the wiring circuit board
Takahiro Ikeda, Osaka (JP); Kyotaro Yamada, Osaka (JP); Taketo Ishikawa, Osaka (JP); Hironori Kuwayama, Osaka (JP); and Yuki Takeda, Osaka (JP)
Assigned to NITTO DENKO CORPORATION, Osaka (JP)
Filed by NITTO DENKO CORPORATION, Osaka (JP)
Filed on Jun. 6, 2023, as Appl. No. 18/330,058.
Claims priority of application No. 2022-096919 (JP), filed on Jun. 15, 2022; and application No. 2022-168719 (JP), filed on Oct. 20, 2022.
Prior Publication US 2023/0413431 A1, Dec. 21, 2023
Int. Cl. H05K 1/05 (2006.01); H05K 1/02 (2006.01); H05K 1/09 (2006.01); H05K 3/40 (2006.01); H05K 3/46 (2006.01)
CPC H05K 1/0298 (2013.01) [H05K 1/05 (2013.01); H05K 1/09 (2013.01); H05K 3/4038 (2013.01); H05K 3/4673 (2013.01); H05K 2201/0338 (2013.01); H05K 2201/09563 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A wiring circuit board comprising: a metal supporting layer; a first metal thin film disposed on the metal supporting layer; an insulating layer disposed on the first metal thin film and including a through hole; a second metal thin film disposed on the insulating layer and also disposed on the first metal thin film in the through hole; and a conductive pattern disposed on the second metal thin film and electrically connected to the metal supporting layer through the first metal thin film and the second metal thin film in the through hole, wherein the first metal thin film includes a first contact surface in contact with the insulating layer and a second contact surface in contact with the second metal thin film, wherein an oxide coating formed by oxidization of the first metal thin film exists at least on the first contact surface, and wherein in a central part of the through hole, the oxide coating either does not exist on the second contact surface, or the oxide coating on the second contact surface is thinner than the oxide coating on the first contact surface.