Infrared Study of Tris(dimethylamino)silane Adsorption and Ozone Irradiation on Si(100) Surfaces for ALD of SiO[sub 2]

Adsorption of tris(dimethylamino)silane { , TDMAS} and decomposition of the adsorbed TDMAS with an ozone ambient on Si(100) surfaces as an atomic layer deposition (ALD) process of have been investigated using Fourier transform infrared absorption spectroscopy (IRAS) with a multiple internal reflection geometry. TDMAS dissociatively adsorbs on the Si(100) surface to produce adsorbates including hydroaminocarbons and Si hydrides even at room temperature. IRAS suggests that TDMAS adsorbs preferentially on OH sites on Si surfaces that are produced by an adsorption. Ozone oxidizes TDMAS adsorbed on the Si surface and makes the surface active to further TDMAS adsorption to progress the ALD cycle. The mechanism of ALD process with TDMAS and ozone is discussed in this paper.