PURPOSE: To utilize a base film efficiently and obtain an IC module with high economic efficiency by providing an aperture forming process, a pattern forming process and an IC chip mounting process.

CONSTITUTION: Two apertures 1b for accommodating IC chips are formed along the width direction of a film 1 and at the same time perforations 5 for cutting off are formed by a press machine 11. Photoresist is applied and exposed through a mask and, after the patterns of the respective parts of contacts 2 and lead wires 4 are cured, etching is carried out. The regions where the contacts 2 are formed are covered with metal plating resist and Sn plating is applied to the regions for taking out IC chips, in other words, the conductive lead wires 4 and protruded parts 4a of the regions around the apertures 1b for IC chip accommodation. Further, the metal plating resist is applied to the whole surface except the parts of the contacts 2. The IC chips 3 are accommodated by the apertures 1b and, in this state, the respective electrode terminals (Au bumps) of the IC chips 3 are jointed with the protruded parts 4a of the lead wires 4.