HYBRID INTEGRATED CIRCUIT SUBSTRATE

PURPOSE:To prevent an external lead-out electrode from being shortcircuited by a solder penetrating into the gap between an insulating substrate and a printed substrate by a method wherein one of the external lead-out electrodes, which are composed of a part of a film conductor formed on the substrate, formed on the side opposed to the printed substrate is covered with an insulating film. CONSTITUTION:A hybrid integrated circuit substrate is mounted on a printed substrate 11 on which a conductor pattern has been formed, and the hybrid integrated circuit substrate is connected to the conductor pattern 11 with solder 13 at a through-hole provided to the side of the hybrid substrate. In this case, as a film conductor 3 constituting the external lead-out electrode is covered with an insulating film 6 at the rear side of the hybrid integrated circuit substrate opposed to the printed substrate 11, the solder 13 is prevented from penetrating into the gap between the printed substrate 11 and the hybrid semiconductor integrated substrate, and even if penetrates, the solder 13 is prevented from touching the conductor 3 on the rear side. By this setup, even if the space between the adjacent film conductors is very small, a short circuit between them can be prevented.