| 摘要 |
PURPOSE:To provide a large-capacity and high-density static RAM by forming driver transistors and switching transistors in an SOI layer, on opposite sides of which the gate electrodes of the respective transistors are formed. CONSTITUTION:Driver transistors Q3 and Q4 have their gate electrodes 6 on one side of an SOI layer 8, while switching transistors Q1 and Q2 have their gate electrodes on the other side of the SOI layer. The driver transistors and the switching transistors include different gate insulator films 7 and 11. These insulator films can have different thicknesses that are optimal for the respective transistors. This improves the performance of a static RAM. Further, since the restriction on gate position can be relaxed, layout becomes easy, and the spacing between transistors is decreased. |
