| 摘要 |
PURPOSE: To cover a contact region which projects from a diffusion region completely from the diffusion region and thus prevent a leak current by forming the diffusion region which completely covers the reverse surface of the contact region by implanting ions of impurities of the same conductivity type as that of the diffusion region after a contact region has been made for a storage electrode and a diffusion region. CONSTITUTION: At the time of mask alignment, part of a 1st contact region 42 projects from a 1st source area 34. Here, a 2nd source region 48 is formed by the ion implantation of impurities of a 2nd conductivity type from above the 1st contact region 42. At this time, the impurity density of the 2nd source region and the depth of the diffusion region by the ion implantation are adjusted almost to the density and depth of impurities in the 1st source region 34. Consequently, the reverse surface of the 1st contact region 42 is covered completely with the 1st and 2nd source regions of the same conductivity type. |
