With non-contact and contact IC chips becoming common, it is necessary to
mass-produce enormous amount of IC chips, which are utilizable for human beings, animals and plants, commercial products, banknotes, and the like, at low cost. For example, it is necessary to manufacture IC chips to be applied to commercial products, banknotes, and the like at a cost of 1 to several yen per IC
chip, preferably, at a cost less than 1 yen, and it is desired to realize a structure of an IC
chip that can be
mass-produced at low cost and a manufacturing process of the IC
chip. A method of-manufacturing a thin film
integrated circuit device according to the present invention includes steps of forming a peel-off layer over a thermally oxidized
silicon substrate, forming a plurality of thin film
integrated circuit devices over the peel-off layer with a base film interposed therebetween, forming a groove between the plurality of thin film
integrated circuit devices, and separating the plurality of thin film integrated circuit devices by introducing one of a gas and a liquid including
halogen fluoride into the groove to remove the peel-off layer.