This paper reports on the threshold adjustment of NMOS transistors by arsenic ion implantation in the channel region directly into bare silicon just before the gate oxidation. Experimental results showed very good uniformity and reproducibility of the threshold voltages, low body effect, and high mobility values.
IEEE Transactions on Electron Devices. New York. Vol. 28, no. 10 (Oct. 1981), p. 1176-1178