| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a vertical MOSFET having a different threshold voltage without complicating a manufacturing process. SOLUTION: A semiconductor device comprises a buried gate electrode 105 extended in the depthwise direction of a semiconductor substrate, and a surface gate electrode 109 extended onto the surface of the semiconductor substrate. Also the device comprises a first vertical MOSFET Q1 having a vertical channel CHA formed by the buried gate electrode 105, and a second vertical MOSFET Q2 having a lateral channel CHB formed by the surface gate electrode 109. Respective threshold voltages of the first and second vertical MOSFETs are allowed to differ each other, and a vertical MOSFET having a different threshold voltage can be manufactured without newly increasing a mask process to a process for manufacturing a conventional vertical MOSFET having the same threshold voltage. COPYRIGHT: (C)2005,JPO&NCIPI
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