Interface diffusion and reaction between Ti layer and Si3N4/Si substrate

Abstract

AbstractA Ti layer of thickness 270 nm was deposited successfully on the surface of Si3N4/Si substrate using the d.c. sputtering technique. Auger electron spectroscopy (AES) analysis indicates that the Ti layer reduced the native SiO2 layer that existed on the surface of the Si3N4 film to form TiOx and Si species at the interface during deposition. The interface diffusion and reaction between the Ti layer and Si3N4/Si substrate was promoted significantly by annealing treatments in the temperature range 300–700 °C in a high vacuum. At temperatures below 600 °C, only very little silicide formed. With increasing annealing temperature, TiSi species formed rapidly. When the temperature reached 700 °C, both TiSi and TiSi2 species formed in the interlayer. The formation of TiSi and TiSi2 species was governed mainly by the interface reaction when the annealing time was short. Silicon in the interlayer mainly came from the Si3N4 layer at low temperature or a short annealing time, otherwise it mainly came from the depletion of Si substrate at high temperature or a long annealing time. Copyright © 2001 John Wiley & Sons, Ltd.