US Patent 10492306 Circuit board and method for manufacturing same

Provided are circuit board excellent in interlayer adhesion and solder heat resistance, and production method thereof. The circuit board is produced by a method including: preparing a plurality of at least one kind of thermoplastic liquid crystal polymer (TLCP) films, forming a conductor layer on one side or both sides of a film in at least one of the films to obtain a unit circuit board, laminating the films containing the unit circuit board to obtain a stacked material, conducting thermo-compression-bonding of the stacked material under pressurization to a first temperature giving an interlayer adhesion to integrate the stacked material, carrying out structure-controlling thermal treatment by heating the integrated stacked material at a second temperature which is lower than the first temperature and is lower than a melting point of a TLCP having a lowest melting point out of the plurality of TLCP films.