| 摘要 |
PURPOSE: To increase the capacity of a MOS transistor as a capacitor by successively forming layers of an insulating material and conductive material by specifying plugs each of which has an upper surface and at least two side sections after the MOS transistor is formed on the surface of a substrate. CONSTITUTION: After a step for forming a MOS transistor on the surface of a substrate 10 is executed, part of the source/drain area of the transistor is exposed by forming a masking layer 56. Then, after tungsten plugs 62 and 64 are formed, the layer 56 is removed and a conformal layer of an insulating material 66 and a conductive material 68 are formed on the plugs 62 and 64, the transistor, and a separation trench 48. In addition, a planar layer 69 of an insulating material is formed on the conformal layer and interconnection patterns 76 and 78 are formed in the source/drain area and between peripheral circuits. Therefore, the capacitance of a capacitor can be increased without increasing the whole cell area including not only the upper surfaces of the plugs 62 and 64, but also the side faces of the plugs 62 and 64. |
