| 摘要 |
The present invention can increase the storage capacity per unit area of a memory module. Also, the present invention provides a memory module with small power consumption. The present invention applies a transistor which is highly purified and comprises an oxide semiconductor film with a band gap wider than 2.5eV, a silicon carbide film, and a gallium nitride film to a DRAM to extend the sustain period of the potential of a capacitor. Also, the present invention can have N number of capacitors with different memory cell capacities and enabling the capacitors to be respectively connected to N number of data lines to vary the maintenance capacity. |
