Effects of iron contamination of thin oxide breakdown and reliability characteristics

The effect of iron contamination in silicon on the properties of thermally grown thin oxides is studied through electrical modeling and experimental MOSDOT testing. Iron concentration is measured using a surface photovoltage diffusion length measurement technique. Failure mechanisms related to iron contamination are proposed. Contamination limits for various gate oxide thicknesses are defined. Experimental results show that reduction of oxide thickness from 20 nm to 10 nm requires a reduction in iron contamination by 100 times.< >