An IC mounting method and its resulting structure, such as an IC card is provided. An IC card includes a metal plate formed with at least one hole, and an IC chip is located fixed in position in the hole with a filler material filling the gap between the hole and the IC chip. An interconnect pattern is provided on the plate with an electrically insulating film sandwiched therebetween, and the interconnect pattern is in electrical contact with a contact pad of the IC chip. Preferably, the surface of the IC chip on which the contact pad is provided is substantially flush with one surface of the plate. When an electrically insulating film is fixedly attached to a substrate having a hole, in which an IC chip is fixedly provided, by an adhesive agent, the material of the film is selected to be similar to the material of the adhesive agent. In this manner, a contact hole may be formed in registry with a contact pad of the IC chip in the insulating film by one etching step without formation of a stepped portion in the resulting contact hole. Moreover, a film to be later removed is first formed on a substrate, and after providing elements on the film and its supporting structure, a predetermined processing, such as exposure to light, is applied to the film to change its property, thereby causing the elements to be separated away from the film.