Abstract: The authors report the effect of the remote plasma nitridation (RPN) process on characteristics of ultrathin gate dielectric CMOSFETs with the thickness in the range of 18 /spl Aring//spl sim/22 /spl Aring/. In addition, the effect of RPN temperature on the nitrogen-profile within the gate dielectric films has been investigated. Experimental results show that the thinner the gate dielectric films, the more significant effect on reducing the gate current and thinning the thickness of gate dielectric films by the RPN process. Furthermore, the minimum dielectric thickness to block the penetration of B and N has been estimated based on the experimental results. The minimum RPN gate dielectric thickness is about 12 /spl Aring/.