Fluorine-assisted super-halo for sub-50-nm transistors

The potential of using a fluorine-assisted super-halo for sub-50-nm transistors is analyzed for the first time. The capability of producing a super-sharp halo using fluorine is demonstrated by one-dimensional (1-D) SIMS profiles. The added ability to tailor the halo profile using fluorine for different transistor criteria on junction capacitance, tunneling current, V/sub t/ roll-off, and mobility is demonstrated. The impact of the resulting fluorine-assisted halo dopant profile on the transistor characteristics is evaluated using TCAD simulations. Experimental data show that the fluorine-assisted halo process results in lowered junction capacitance and improved I/sub on/-I/sub off/ characteristics for both nMOS and pMOS.