Oxidation Kinetics Of Crystalline Silicon Oxynitride

Abstract

AbstractOxidation stability of silicon oxynitride is a property of great technological significance. In this study, the oxidation behavior of stoichiometric polycrystalline Si2N2O was investigated in 1 and 0.5 atm flowing dry oxygen at 1000°‐1300°C. The oxidized Si2N2O samples were characterized using transmission and scanning electron microscopy. The oxidation kinetics were determined using profilometry in conjunction with patterned etching. Oxidation of Si2N2O resulted in the formation of amorphous SiO2. The SiO2‐Si2N2O interface was chemically and structurally abrupt. A parabolic rate law was followed during oxidation with apparent activation energies ranging from 43 to 52 kcal/mol. The relatively high activation energy values compared to that for silicon oxidation suggest that oxidation of Si2N2O is rate‐controlled by a more complex process than molecular oxygen diffusion in amorphous SiO2.