| 摘要 |
PURPOSE:To realize compactness of a memory cell, easy connecting of a bit line and a short word line by providing a MOS transistor for a cell to one main surface of a semiconductor substrate and by providing a MOS transistor for a transfer gate to a semiconductor thin film provided through an insulating film on the semiconductor substrate. CONSTITUTION:First and second MOS transistors T1, T2 for a cell are provided to one main surface of a semiconductor substrate 21. Third and fourth MOS transistors T3, T4 for a transfer gate are provided to semiconductor thin films 3, 6 which consist of a silicon thin film provided through an insulating film 23 on the semiconductor substrate. Therefore, a connecting part with MOS transistors T1, T3 becomes unnecessary, or a bit line opening part 11 can be provided regardless of shortcircuit with a word line 7 since the word line 7 is separated. Furthermore, in any case, a depth of the bit line opening part 11 becomes shallow as it is only required as far as silicon thin films 3, 6. Thereby, it is possible to realize compactness of a memory cell, easy bit line connection and a short word line. |
