| 摘要 |
PURPOSE:To achieve high degree of integration and large capacitance as well as to contrive sharp reduction in soft error rate and the leak current of the titled memory device by a method wherein a trench is formed between the two word wires on a memory cell, an interlayer insulating film is formed on the word wires and the inner wall of the trench, and a capacitor of stack structure is formed on the interlayer insulating film and a field oxide film. CONSTITUTION:A capacitor is formed between a plate electrode 6 and the conductive electrode 9 whereon the source part of a memory cell with be formed. A storage capacitor consists of the part, which is buried in a trench, and other part located on the plane surface, and pertaining to the part in the trench, as all the side face of a third electrode is used as the capacitor, the capacitance of the storage capacitor can be increased extremely. Also, the area of the source part is made small as much as possible, the P-N junction region located between the source diffusion part of the memory cell and the substrate can be reduced, the leak current of the memory cell can be reduced substantially, and the soft error of alpha rays can also be reduced drastically. |
