ELECTRONIC CIRCUIT DEVICE

摘要

The purpose of the present invention is to improve the heat dissipation effect of a conductor layer while suppressing breakage of a substrate along the boundary plane between an insulating layer and the conductor layer. An electronic circuit device (100) comprises an insulating layer (1), a conductor layer (2) formed on at least one side of the insulating layer (1), and a heating element (4) disposed on the side of the conductor layer (2) opposite from the insulating layer (1) with a joining layer (3) interposed therebetween. The conductor layer (2) comprises a heat dissipating conductor layer (21) located on the heating element (4) side and a circuit layer (22) located on the insulating layer (1) side. On the boundary plane between the heat dissipating conductor layer (21) and the circuit layer (22), the shortest distance (l1) from the side edge section of the heating element (4) to the side edge section of the heat dissipating conductor layer (21) is equal to or greater than the thickness (t1) of the heat dissipating conductor layer (21).