MOS transistor with assisted-gates and ultra-shallow amp;ldquo;Psuedoamp;rdquo; source and drain extensions for ultra-large-scale integration

摘要

A MOS transistor and a method of fabricating the same for Ultra Large Scale Integration applications includes a composite gate structure. The composite gate structure is comprised of a main gate electrode and two assisted-gate electrodes disposed adjacent to and on opposite sides of the main gate electrode via an oxide layer. Areas underneath the two assisted-gate electrodes form ultra-shallow “pseudo” source/drain extensions. As a result, these extensions have a more shallow depth so as to enhance immunity to short channel effects.