| 摘要 |
PURPOSE:To lower the value of contact resistance and reduce dispersion by shortening each electrode to the transistor having the structure of two active layers, and, for the lower layer transistor, removing the interface between a columnar electrode and a pedestal electrode. CONSTITUTION:After formation of lower layer transistors 5, 6, and 7, a silicon oxide film 3 to become a first insulating film is formed. Subsequently, upper layer transistors 5a, 6a, and 7a are formed, and the whole face is covered with a second silicon oxide film 4 to become a second insulating film. Next, by the exposure process using a photoresist and the dry etching process, to the upper layer transistor, a second contact hole, in the silicon oxide film 4, and to the lower transistor, a first contact hole, in the silicon oxide film 3, are formed, and then only in the first contact hole, a columnar electrode 8a by tungsten is formed. Lastly, aluminum is deposited, and wirings 10 are formed the columnar electrode 8a and in the second contact hole of the upper layer transistor. |
