| 摘要 |
PURPOSE:To provide an excellent resistance against a software error by forming a capacity by digging a groove on an Si substrate at a signal storage node of a flip-flop in a memory cell, and forming a drive MOSFET and a load resistor. CONSTITUTION:A deep groove is formed on a P-type Si substrate 10 before or after a trench isolating region 11 is formed on the substrate, a P<+> type diffused region 30 is formed on its sidewall, a thin SiO2 film 31 is formed substantially on a whole surface including the groove, and a polysilicon film 32 is buried in the groove. The film 32 is connected to an N<+> type diffused region 17', and also connected to the gate electrode 16 of a drive MOS FET. Thus, a large capacity is added to the substrate formed of the films 32, 31 formed in the grooves with nodes N1, N2 and the substrate 10. Since large capacities C1, C2 are added to the nodes N1, N2, a resistance against a software error can be preferably improved. |
