| 摘要 |
The present invention contemplates a highly reliable semiconductor memory device. The semiconductor memory device includes a silicon substrate containing a p impurity of a first concentration, an epitaxial layer formed at the silicon substrate and containing a p impurity having a second concentration lower than the first concentration, a memory region provided on the epitaxial layer, and a logic circuit region provided on the epitaxial layer at a location different from the memory region. The memory region includes a p well, an n well and a bottom well. The logic circuit region includes a complementary field effect transistor. |
