| 摘要 |
PROBLEM TO BE SOLVED: To suppress a sub threshold current and a tunneling leakage current, while keeping the threshold voltage of a transfer gate as it is. SOLUTION: A semiconductor IC comprises a p-type semiconductor layer 18 selectively formed in the surface of a semiconductor substrate 11, a p-type channel doped layer 39 selectively formed in the surface of the semiconductor layer, gate electrodes 21, 22 of MOSFETs for the transfer gate of a DRAM cell formed on the semiconductor layer via a gate insulation film 20 as to correspond to the channel-doped layer, n type source and drain regions 24 selectively formed in the surface of the semiconductor layer between the gate electrodes, and a cell capacitor having an electric charge storage node 16, which is connected to either the source or the drain region, The p-type impurity concentration profile of the channel doped layer is such, that the concentration is high near the central axes of the gate electrodes and is low near an interface between the channel doped layer and the source and drain regions. |
