| 摘要 |
PURPOSE:To enable a size of a memory cell to be reduced, without deteriorating the stability of the read operation of the data accumulated in the memory cell, by constituting all transistors with thin film transistors. CONSTITUTION:On the principal surface of a silicon substrate 32, an insulation layer 33a is formed. On the surface of the insulation layer 33a, a pair of access transistors Q3 and a pair of driver transistors Q1 are provided. These four transistors Q1, Q3 are constituted with n-type thin film transistors. Also, the surfaces of these four transistors Q1, Q3 are covered with a first interlayer insulation layer 33b. On the surface of the first interlayer insulation layer 33b, a pair of p-type load transistors Q5 is formed. In this manner, since all the six transistors of a memory cell are formed with thin film transistors, the threshold values of the access transistors can be prevented from increasing by a channel narrowing effect. |
