| abstract |
(57) [Summary] There is a circuit device in which a circuit element is mounted as a support substrate using a printed circuit board, a ceramic substrate, a flexible sheet, or the like. However, these supporting substrates are unnecessary materials and are extra materials. In addition, there is a problem that the thickness of the supporting substrate increases the size of the circuit device. SOLUTION: After forming a separation groove 54 in a conductive foil 60, The circuit elements are mounted in a flip-chip manner, and the conductive foil 6 0 is used as a supporting substrate, the insulating resin 50 is applied, and after inversion, a conductive foil is polished using the insulating resin 50 as a supporting substrate and separated as conductive paths. Therefore, a circuit device in which the conductive path 51 and the circuit element 52 are supported by the insulating resin 50 can be realized without using a supporting substrate. |