| 摘要 |
PROBLEM TO BE SOLVED: To prevent an IC card from being illegally used even when the information of a sum in a flash memory is altered by mechanically, physically, or chemically performing access, and exposing the surface of an integrated circuit. SOLUTION: A capacitor 3 is overlapped on the upper part of the integrated circuit of an IC chip 2. Thus, it is necessary to destroy the capacitor 3 for altering the information of a sum in a flash memory through mechanically, physically or chemically accessing resulting in exposure of the surface of the integrated circuit and it is not possible to use an IC card 5' after alternation. Also, the dielectric of the capacitor 3 is made of strontium titanate, and formed at 400 deg.C by using an electronic cyclotron resonating device. |
