AbstractWe propose a new parameter predicating transconductance (Gm) of the gate dielectric of nitrided SiO2 with the physical thickness below 1.1 nm for high-performance transistors. The 6 different type of nitrided SiO2 are formed using the plasma nitridation or nitric oxide (NO) gas annealing in conditions to adjust a optical thickness ranging 0.96 to 1.19 nm. The material property of nitrided SiO2 are analyzed by secondary ions mass spectroscopy (SIMS) and x-ray photoelectron spectroscopy (XPS). The MOSFET are fabricated using these gate dielectric and 90 nm generation CMOS technology. Then we find a good correlation between the maximum of Gm and the percentage of amount of N(SiN3)3 substructure at the total amount of NSi3 structure measured by XPS, rather than the total dose of nitrogen measured by SIMS.