摘要 |
Data is written in the following manner: potentials of first and second control gates of a transistor are set at a potential for making a storage gate of the transistor a conductor, a potential of data to be stored is supplied to the storage gate, and at least one of the potentials of the first and second control gates is set at a potential for making the storage gate an insulator. Data is read in the following manner: the potential of the second control gate is set at a potential for making the storage gate an insulator; a potential is supplied to a wiring connected to one of a source and a drain of the transistor; then, a potential for reading is supplied to the first control gate to detect a change in the potential of a bit line connected to the other of the source and the drain. |