| 摘要 |
PURPOSE:To realize a simply structured memory cell without using a capacitor and to obtain a semiconductor device which is small in cell area and capable of executing a memory function sufficiently by a method wherein a second MOS transistor is formed on a single crystal semiconductor layer formed on a first MOS transistor through the intermediary of an insulating film and other processes are executed. CONSTITUTION:A first MOS transistor is formed on a primary face of a semiconductor substrate 10, highly concentrated impurity diffusion regions 24 and 25 are provided apart from a single crystal semiconductor layer 20 by a specified distance, where the layer 20 is formed on the first MOS transistor through the intermediary of insulating films 11, 12, and 16, and a second MOS transistor, provided with an electrode 23 formed on a channel region which is sandwiched in between the diffusion regions 24 and 25, is provided. And, the channel region of the above second MOS transistor is arranged just above an impurity region 14 of the impurity regions of the first MOS transistor, and the thickness of a semiconductor layer of the second MOS transistor channel region is so set as to enable the channel region to be completely depleted when the second MOS transistor is in operation. |
