| 摘要 |
PURPOSE:To eliminate abnormal operation relating to a substrate potential, by providing a switching element having a highly doped source or drain electrode of a first conductivity type, substantially vertically to the substrate. CONSTITUTION:When a high voltage is applied to a gate electrode 14, a depletion layer 54 extending below the gate electrode can electrically isolate N<+>-type doped layers 15, 17 arranged on and under a transistor from each other. When a low voltage is applied to the gate electrode 14, the depletion layer 54 is made small and the N<+>-type doped layers 15, 17 on and under the transistor are electrically connected with each other. The transistor is of the type in which the carriers flow through the substrate 11 and operates completely independent of a potential of the P-type Si substrate 11. In this manner, stable operation of the memory can be obtained without causing any abnormal operation. |
