PURPOSE: To obtain a hybrid IC having high reliability by sealing a printed circuit board with one or more layers of radio wave absorbing resin to prevent noises between lines and circuit parts in the IC from rounding about.

CONSTITUTION: A semiconductor element 4 and a driven element 5 are placed on an epoxy substrate 2, coated with an Si resin 6 and the first radio wave absorbing resin 7 to prevent noises from rounding about, and contained in a housing 1. Then, resins 8W12 are sequentially packed in the housing, cured, and the substrate 2 and lead pins 3 are secured. Since at least one of the resin layers is disposed as the innermost layer as the radio wave absorbing layer, it is extremely effective. When carbon or metal piece is mixed in the resin, a high frequency current flows to the surface layer to attenuate the radio wave. When a ferrite is mixed, it prevents lines of magnetic force to interrupt the radio wave. The surfaces of the lead pins are coated with insulating films to prevent them from short-circuiting with conductive resin, various radio wave absorbing materials are used together to obtain a hybrid IC which interrupts the all radio waves.