Semiconductor device where logic region and dram are formed on same substrate

Abstract

A semiconductor device having a DRAM region and a logic region embedded therein, includes: a substrate having the DRAM region and the logic region respectively formed thereon; a first transistor formed in the DRAM region, and having a first gate insulating film, and a second transistor formed in the logic region, and having a second gate insulating film, wherein equivalent oxide thickness Tof the first gate insulating film of the first transistor is not larger than equivalent oxide thickness Tof the second gate insulating film of the second transistor, the second transistor formed in the logic region has a pocket region which contains an impurity ion having a conductivity type different from that of an impurity ion composing the source/drain regions, while the first transistor formed in the DRAM region has no pocket region.