Properties of silicon dioxide films prepared by pulsed-laser ablation

Abstract

Silicon dioxide films have been prepared by ArF pulsed-laser ablation of a silicon monoxide (SiO) target in oxygen atmosphere at various substrate temperatures (20–450 °C). The structural and electrical properties of the SiO2 deposited films have been investigated. The experimental results indicate a strong reduction of the porosity and structural defects in the films for increasing values of the deposition temperature. Film properties are also strongly influenced by the application of post rapid thermal (400–1000 °C) treatments in Ar atmosphere. The refractive index of these films increases, whereas we observe a reduction of their relative dielectric constant which is mainly attributed to the diminution of the amount of hydrogen trapped into the laser grown oxide. A minimum oxide charge density of 1.5×1011 cm−2 with a dielectric breakdown field of 2–8 MV/cm was measured in oxide films deposited at 20 °C and subsequently annealed at 1000 °C by rapid thermal treatment (30 s).