PROBLEM TO BE SOLVED: To satisfy a constraint condition in manufacturing while mounting an electronic component in high density.SOLUTION: A flexible substrate of one embodiment is provided with: a unit substrate including a plurality of surface electrodes that are provided on the surface and mount electronic components, reverse surface electrodes that are provided on the reverse surface and connected to any of the surface electrodes, and a plurality of conductive layers that is provided inside and connects the surface electrodes with a terminal provided on an end surface and an extension unit substrate which is disposed on the reverse surface side of the unit substrate via an anisotropic electroconductive film and includes a surface auxiliary electrode provided at a position opposite to the reverse surface electrode, and a plurality of conductive layers that is provided inside and connects the surface auxiliary electrode with a terminal on an end surface.COPYRIGHT: (C)2016,JPO&INPIT【課題】電子部品を高密度に搭載しながらも、製造上の制約条件を満たすこと。【解決手段】実施形態のフレキシブル基板によれば、表面に設けられ電子部品を搭載するための複数の表面電極、裏面に設けられ前記表面電極のいずれかと接続された裏面電極、内部に設けられると共に、前記表面電極と端面に設けられた端子とを接続する複数の導電層が形成されたユニット基板と、このユニット基板の裏面側に異方性導電膜を介して配置され、前記裏面電極に対向する位置に設けられた表面補助電極、内部に設けられると共に、前記表面補助電極と端面に設けられた端子とを接続する複数の導電層が形成された増設ユニット基板とを備えている。【選択図】図2
