摘要 |
A semiconductor memory device has a first ferroelectric memory cell in which data is written after the device is mounted on a board, and a second ferroelectric memory cell whose capacitance is larger than that of the first ferroelectric memory cell. This second ferroelectric memory cell is utilized as a memory cell in which cipher or the like are written in the fabrication process. The second ferroelectric memory cell is formed with a combination of a plurality of the first ferroelectric memory cells. In order to realize the second ferroelectric memory cell, word lines or plate lines corresponding to a plurality memory-cell rows may be short-circuited. Alternatively, bit lines corresponding to a plurality memory-cell columns may be short-circuited.
|