PURPOSE: To obtain the hybrid IC of superior performance at a low price by a method wherein circuit parts necessitating to be formed with thin films are formed with thin film circuits and other circuit parts are formed with thick film circuits, and these are made in the hybrid.

CONSTITUTION: When the hybrid IC is to be formed, a substrate 4 having at the back face thick film circuits formed by printing of conductive paste like palladium, silver, etc., is put on a header 1 and is soldered using a solder material 3 made of lead and tin. A thin film circuit substrate 5 being formed with a fine conductor circuit pattern like a spiral coil, etc., and bonding pads, and having golden metallized layer at the back face, is soldered on the header 1 in the same way adjoining to the substrate 4. Then the substrates 4 and 5 are connected with bonding wires 6 to constitute a hybrid IC. Or the substrate 5 may be fixed on the substrate 4 being separated from the substrate 4. By this way, as only the fine pattern part, high frequency circuit part, which are unable to be formed in thick film, are made in thin film, and others are made in thick film, the circuit can be produced at a low price without the drop of performance.