THE EFFECT OF FLUORINE ON MOSFET CHANNEL-LENGTH

The effect of fluorine on MOS device channel length has been evaluated in this investigation. In this study, fluorine has been introduced in to the transistor in a different manner compared to other studies on f luorinated devices, by self-aligned ion implantation after the lightly doped drain (LDD) implant. The impact of fluorine in the LDD region, and its effect on the electrically determined channel length (L(eff)), has been examined. Measurements taken from 0.6-mum LDD MOSFET's show a significant dependence of the L(eff) on fluorine implant dose. The n + resistor also shows less width increase compared to unfluorinated sa mples. The decrease in channel length reduction by adding fluorine in the LDD region may yield a way to relieve short-channel effects for th e continuous scaling of CMOS devices into the deep-submicrometer regio n.