| 摘要 |
PURPOSE:To reduce the area of a memory cell by a method wherein the source region on the surface of a substrate and the wiring on the source are unnecessitated by forming the source of an MOSFET with the buried layer located in the substrate. CONSTITUTION:The source of a driver MOSFET Q1 is formed by supplying ground potential to the n-type high impurity concentration buried layer 103 provided in a p-type substrate 10. Said layer 103 can be formed by ion- implanting n-type high concentration impurities into the surface of the substrate 10, and also by accumulating a silicon single crystal on an n<+> layer using an epitaxial growing method. The drain region 7 of the FET Q1 is made common with a source 6, and it is formed in a p-well 9. The gate electrode 102 of the FET Q1 is formed by providing a groove in the region 7, by forming a gate oxide film 101 in the groove and also by burying polysilicon inside the groove. |
