| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a DRAM element, which can obtain the stabilization of an etching process. SOLUTION: A DRAM element of a constitution, wherein capacitors 69, 71 and 72 and a bit line 78 are respectively formed on the opposite surface to the surface of a silicon layer and a parasitic electrostatic capacity between the above capacitors 69, 71 and 72 and the above bit line 78 is thoroughly prevented, is manufacturing almost as follows. First and second trenches are respectively formed in a second silicon layer 62 and an element isolation film 63, first and second impurity layers 67a and 67b are formed in both sides of the second trench, a third impurity layer 67c is formed in the bottom of the second trench, a fourth impurity layer 67d is formed in the bottom of the first trench, a first coupling wiring 70, which is linked to the layer 67d, and the capacitors, which are linked to the layers 67a and 67b, are formed on a first interlayer insulating film, a second coupling wiring 74, which is linked to the wiring 70, is formed in a second interlayer insulating film 73, a bit line 78, which is linked to the layer 67c, and a third coupling wiring 97, which is linked to the wiring 70 via the layer 67c, are formed in a buried oxide film 61 and a fourth coupling wiring 81, which is linked to a wiring 79, is formed in a fourth interlayer insulating film 80. |
