| 摘要 |
PURPOSE:To reduce the leakage current of a charge pumping type memory cell by employing a bulk silicon semiconductor substrate and reduce the cell area to a minimum by employing a buried source type. CONSTITUTION:An N-type layer 32 is formed on an N-type silicon semiconductor substrate 30 to form an isolation field oxide film 34 thereon. Further, a gate electrode 38 and a gate oxide film 40 are formed. A P-type impurity is diffused through an opening W of the gate oxide film 40, an N-type impurity is further diffused to form a P-type layer 42 and an N<+>-type layer 44 thereon. Thereafter, an insulating film 46 is attached thereto, aluminum is then coated thereon, and is patterned to form a bit wire 48. A word wire is formed of the extension of the gate electrode 38. The layer 32 to become a source region makes electric contact with the substrate 30, which becomes a common source wire. |
