| 摘要 |
PURPOSE:To make it possible to respond to a capacity maintenance demand accompanying reduction in memory cells to a satisfactory extent by forming a trench capacity which is separated with an insulation block including an insulation film on a second trench and the side and the bottom of the second trench form the bottom of the first trench further at its depth. CONSTITUTION:A second trench 5a is formed at a substrate at a further depth from the bottom of a first trench 2a. An insulation film 6, such as silicon oxide is installed on the surface of the second trench 5a where its internal part is filled with polysilicion or a BPSG film. |
