SRAM DEVICE

摘要

In an SRAM device, a four-terminal double gate field effect transistor is used as a selection transistor. The four-terminal double gate field effect transistor has a gate for driving the transistor and a gate for controlling a threshold value, which are electrically separated, on the both surfaces of a standing semiconductor thin board. While writing operation is performed, a voltage to reduce the threshold voltage from the threshold voltage for reading is inputted to the gate for controlling the threshold value of the selection transistor, and both of a write margin and a read margin can be increased.