METAL-BASE CIRCUIT BOARD AND ITS MANUFACTURING METHOD

摘要

A metal-base circuit board enables significant reduction of failures of a semiconductor device occurring in high-frequency operation of a hybrid integrated circuit and has an excellent heat dissipation capability. A metal base circuit board used for hybrid integrated circuits comprises a circuit provided over a metal sheet with insulating layers (A, B) interposed therebetween, an output semiconductor device mounted on the circuit, and a control semiconductor device used for controlling the output semiconductor device and mounted on the circuit. The metal-base circuit board is characterized in that a small-capacitance portion is buried under the circui t portion (pad portion) on which the control semiconductor device is mounted, and preferably the small-capacitance portion is made of a resin containing a n inorganic filler and has a dielectric constant of 2 to 9.