Nature of the mechanism of interface state creation on electrically stressed metal-oxide-semiconductors structures

Abstract

The defects generated at the Si-SiO2 interface by electron injection across the oxide under high electric-field stress conditions are studied as a function of the stressing temperature in the range 100–450 K. After stress at temperatures below 300 K, the interface state creation during isochronal annealing at room temperature is analyzed. The defect formation is readily explained by the diffusion of neutral hydrogen-related species and a simple model allows the determination of its diffusion coefficients to be in the range of 1.0×10−14–4.2×10−14 cm2 s−1 at 200 K to 1.6–6.6×10−12 cm2 s−1 at 275 K. These values are in good agreement with the extrapolated values from the known data for the hydrogen diffusion in SiO2 determined at higher temperatures.