| 摘要 |
PURPOSE:To prevent generation of a soft error caused by alpha rays by a method wherein a conductive layer of the same conductive type as a substrate having the density higher than that of a substrate is formed on an impurity region in such a manner that at least one end of the conductive layer is not overlapped. CONSTITUTION:A field 2 and a gate electrode 4 are formed on a P-type silicon substrate 1, and an oxide film 5 is formed. Then, an etching is performed on the whole surface leaving the side face only of the gate electrode 4 whereon the oxide film 5 is thickly formed. Subsequently, boron is ion-implanted, and P-type diffusion layers 6 and 7 are formed. Then, the oxide film on the side face of the gate electrode 4 is removed, arsenic of high density is implanted shallower than the P-type diffusion layer region which is already formed, an N-type diffusion layers 8 and 9 formed. |
