HIGH-FREQUENCY MODULE BOARD DEVICE

摘要

A high−frequency module board device equipped with a high−frequency transmitting/receiving circuit for modulating/demodulating a high−frequency signal has a base substrate (2) the main face of which is constituted as a build−up face (2a) and a high−frequency circuit section (3) which overlies the build−up face of the base substrate (2) and incorporates a passive element. The base substrate (2) comprises a wiring−free region (29) below a fourth wiring layer (8b). The high−frequency circuit section (3) has an upper electrode section (36) and a lower electrode section (35) at a position corresponding to the wiring−free region (29) and thereby has a capacitor (18) immediately above the wiring−free region (29). Thus, the parasitic capacitance, which the capacitor (18) receives from a ground pattern (14), is reduced, so that the characteristics of the capacitor (18) are improved.