A folded-channel MOSFET for deep-sub-tenth micron era

Deep-sub-tenth micron MOSFETs with gate length down to 20 nm are reported. To improve the short channel effect immunities, a novel folded channel transistor structure is proposed. The quasi-planar nature of this new variant of the vertical double-gate SOI MOSFETs simplified the fabrication process. The special features of the structure are: (1) a transistor is formed in a vertical ultra-thin Si fin and is controlled by a double-gate, which suppresses short channel effects; (2) the two gates are self-aligned and are aligned to the S/D; (3) S/D is raised to reduce the parasitic resistance; (4) new low-temperature gate or ultra-thin gate dielectric materials can be used because they are deposited after the S/D; and (5) the structure is quasi-planar because the Si fins are relatively short.