PURPOSE: To improve reliability by forming a boundary region between a wiring conductor layer and a connecting section in the conductive layer of a single layer or multilayers thicker than the wiring conductor layer adjacent to the boundary region.

CONSTITUTION: Silver palladium conductor paste is printed onto a crossover glass layer 14 while silver palladium conductor paste is also printed into a boundary region between a wiring conductor layer 13 and a connecting section 12, and the paste is baked, thus simultaneously a cross wiring conductor layer 15 and a boundary-region conductor layer 16. The greater part of the boundary- region conductor layer 16 are arranged on the wiring conductor layer 13 side, and a residual slight section is disposed on the connecting section 12 side. Since the boundary region is shaped in two layer structure in which the wiring conductor layer 13 and the connecting section 12 are used as a first layer and the boundary-region conductor layer 16 as a second layer, the thickness of the boundary region is made thicker than that of a region adjacent to the boundary region. Accordingly, disconnection in the boundary section between the connecting section 12 and the wiring conductor layer 13 is prevented, thus acquiring o circuit substrate device having high reliability.