Atomic Layer Deposition of Silicon Oxide Thin Films by Alternating Exposures to Si[sub 2]Cl[sub 6] and O[sub 3]

We report the process for the atomic layer deposition (ALD) of silicon dioxide thin films on a silicon wafer by alternating exposures to Si 2 Cl 6 and O 3 . The deposition was governed by a self-limiting ALD reaction at 403 – 453 ° C , and the growth rate at 453 ° C was saturated at 0.32 nm ∕ cycle for Si 2 Cl 6 exposures over 1 × 10 8 L . However, at 471 ° C or higher temperatures, the thermal decomposition of Si 2 Cl 6 and the oxidation of Si by O 3 dominated the deposition, resulting in high growth rates and Si-rich films. The ALD films exhibited excellent electrical properties that were equivalent to those of low-pressure chemical vapor deposition films.