| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a new method of manufacturing a semiconductor device including a transistor having a trench gate structure and a transistor having a planar gate structure on the same substrate, wherein depletion can be prevented by introducing a sufficient amount of dopant into polysilicon of the trench gate even if it employs a polymetal gate structure for a gate electrode structure and has a dual gate structure wherein the trench gate and the planar gate have different conductivity types and punchthrough of impurity ions through a gate insulation film can be prevented even if a polysilicon layer of the planar gate has such a thickness that usually causes punchthrough of impurity ions through the gate insulation film. <P>SOLUTION: Ions are introduced into a silicon layer for the trench gate. Thereafter, the silicon layer is turned into a polysilicon layer once. Then, ions are introduced again into the polysilicon layer to turn the surface amorphous (layers 9 and 10). Then, ions having a different conductivity type are introduced for the planar gate. <P>COPYRIGHT: (C)2008,JPO&INPIT |
