A Comparison of Short-Channel Control in Planar Bulk and Fully Depleted Devices

The short-channel effects (SCEs) of planar bulk and fully depleted finFET devices have been compared using the same junction overlap and lateral gradient, and it is shown that, for finFET devices, a significant component of electrostatic control arises from a naturally present shallow extension junction. When such shallow junctions are applied to a bulk device, we show that the SCE becomes comparable to that of a finFET. Furthermore, we show that, if an embedded source/drain stressor is incorporated in a bulk device, it will not degrade the short-channel benefit of the ultrashallow junctions. The ability to span a wide power/performance range by doping and the improvement in SCEs by the use of ultrashallow extension junctions can potentially extend the life of bulk-type technologies.