| 摘要 |
PURPOSE:To make possible high density integration by reducing a memory cell area. CONSTITUTION:A semiconductor storage device has a capacitor provided with a transverse direction enlargement part 17 in a lower part of a trench 16, and a transistor, an isolation region, etc., are provided above the transverse direction enlargement part, thus improving integration degree. The transverse direction enlargement part is formed by etching in a silicon oxide film 12 sandwiched between a substrate and a silicon layer and can be acquired as a recessed part formed in advance in a semiconductor substrate. A silicon layer is laminated on a semiconductor substrate wherein such a recessed part is formed or another semiconductor substrate is adhered. A desired trench capacitor can be acquired by forming a trench reaching the recessed part and forming a specified film. An oxide film is formed all over a semiconductor substrate wherein the recessed part is formed or in the recessed part to improve insulation property. Influence of radiation can be eliminated in this way. |
