| 摘要 |
PURPOSE:To eliminate a problem that an electric field applied to a PN junction between a substrate and a source.drain layer of a transfer gate transistor in a memory cell of a semiconductor storage device, in paticular, a DRM increases, a junction current becomes large, and the data holding time of the memory cell deteriorates. CONSTITUTION:Under an active region in which a transfer gate transistor 51 or the like is formed, an impurity layer 5 different from a source.drain layer is formed at a deep position in a substrate 1, away from the substrate surface. |
