| 摘要 |
PURPOSE:To decrease channel leak current flowing between a pair of semiconductors area which are provided separately, by a method wherein while electric current is not conducted in a switching element, an inverted layer which is formed at the main surface part of a first semiconductor area of the lower part of a polycrystal silicon layer, is canceled. CONSTITUTION:A switching element 4X is formed by an n<-> type semiconductor area 12, an n<+> type semiconductor area 13, an insulation film 14, a pair of p<+> type semiconductor areas 15, and a channel area 16. Said element 4X is composed of a p-channel type MISFET construction making the semiconductor area 12 as a gate electrode, and the semiconductor area 13 as a source area and drain area. For instance, after the semiconductor area 12 is formed, a mask for newly forming the semiconductor area 13, is formed on a semiconductor substrate 6, and the semiconductor area 13 is formed by introducing n type impurities in the main surface of the semiconductor substrate 6 by ion implanting. When information are read out, since an H level potential is applied to the semiconductor area 12 which becomes the gate electrode, light enable signal-WE at the time of read-out being H level, the element 4X becomes non-conducting condition. Because the semiconductor area 13 having high impurities density is provided at the main surface part of the semiconductor area 12, the formation of an inverted layer at the main surface part of the semiconductor area 12 can be prevented while the element 4X is not conducted, so the flowing of channel leak current between a pair of semiconductor areas 15 which becomes a source area and drain area can be prevented. |
