| 摘要 |
PURPOSE:To enable good data-holding characteristic and high reliability to be obtained, by making at least a drain area of an access transistor a LDD structure or a DDD structure, and by composing at least a drain area of a driver transistor of only an area with relatively high impurity concentration. CONSTITUTION:A memory cell consists of a flip-flop circuit having driver transistors 11, 12 and a switching circuit having access transistors 13, 14. In such a semiconductor memory device, at least each of drain areas 23f, 23g of access transistors 13, 14 is composed of a first area with relatively low impurity concentration which is so disposed as to be close to a channel area, and a second area with relatively high impurity concentration which is disposed more apart from the channel area compared with the first area. And, at least each of drain areas 23b, 23d of driver transistors 11, 12 is composed of only a third area with relatively high impurity concentration. |
