| 摘要 |
PURPOSE: To provide a semiconductor storage device having high reliability. CONSTITUTION: The semiconductor storage device comprises a silicon substrate 109 containing a p-type impurity in a first concentration, an epitaxial layer 108 formed on the substrate 109 and containing a p-type impurity in a second concentration lower than the first concentration, a storage area 191 provided on the layer 108, and a logic circuit region 192 provided at a different position from the area 191 on the layer 108. The storage area 191 includes a p-type well 105, an n-type well 113, and a bottom well 102. The logic circuit region 192 includes a complementary field effect transistor. |
