US Patent 7910988 Semiconductor device and manufacturing method therefor

A semiconductor device including a trench-gate MOS transistor on a semiconductor substrate is constituted of a trench formed in an active region, a fin channel region formed between a separation region and the trench in the active region, a first gate electrode embedded in the separation region in connection with the fin channel region via a first gate insulating film, a second gate electrode embedded in the trench in connection with the fin channel region via a second gate insulating film, and a source-drain diffusion region disposed beside the trench in the active region below the second gate electrode.