| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that the thickness of a retaining substrate makes a circuit device large, in a circuit device wherein circuit elements are mounted by using a printed board, a ceramic substrate, a flexible sheet, etc., as the retaining substrate, which is essentially unnecessary and superfluous material. SOLUTION: After isolation trenches 54 are formed in a conducting foil 60, circuit elements are mounted, and insulating resin 50 is stuck on the conducting foil 60 which is made the retaining substrate. After inversion, the conducting foil is polished and isolated as conducting paths by using the insulating resin 50 as the retaining substrate. As a result, a circuit device wherein the conducting paths 51 and the circuit elements 52 are retained by the insulating resin 50 can be realized, without adopting the retaining substrate. |
