| 摘要 |
PROBLEM TO BE SOLVED: To properly suppress high concentration of a substrate and to improve a retention characteristic without increasing a manufacture process by including not only the transistors of a memory cell but also transistors used in a peripheral circuit and using p-type polysilicon as gate electrodes. SOLUTION: Since a polysilicon film 32 constituting the gate electrodes of the respective transistors is formed by covering a silicon oxide film 30 and the polysilicon film 32 becoming the gate electrode in a subsequent stage is set to be the p-type polysilicon film, BF2 ions are driven. Then, a silicon oxide film 34 is formed by covering the p-type polysilicon film 32. Then, a patterning processing for forming the gate electrode 32 of the nMOS transistor of the memory cell, the gate electrode 32b of the nMOS transistor of the peripheral circuit and the gate electrode 32c of the pMOS transistor is executed. The respective source/drain areas of the nMOS transistors of the memory cell and the nMOS transistors of the peripheral circuit are formed. |
