Reduced 1/f noise and g/sub m/ degradation for sub-0.25 /spl mu/m MOSFETs with 25 /spl Aring/-50 /spl Aring/ gate oxides grown on nitrogen implanted Si substrates

We introduce a light dose of nitrogen implant (N/sup +/ I/I) into the Si substrate before growing the oxides, and incorporated /spl sim/3-4 atomic% of nitrogen in the oxides. Consequently, the 1/f noise is reduced by a factor of 2-5, and the g/sub m/ degradation is reduced by a factor of 5. The N/sup +/ I/I does not affect the oxide breakdown field which continues to follow the hole-trap model as the oxide thickness reaches 25 /spl Aring/ in this experiment. MOSFETs of 0.2 /spl mu/m physically are then fabricated with 25 /spl Aring/ oxides on N/sup +/ I/I substrates.