Metalorganic Chemical Vapor Deposition of Al2O3 Thin Films from Dimethylaluminumhydride and O2

Abstract

Metalorganic chemical vapor deposition (MOCVD) of Al2O3 thin films using dimethylaluminumhydride (DMAH) and O2 as precursor and oxidant, has respectively been performed on Si substrate. Compared with some reported results, Al2O3 films with low carbon content and suppressed interfacial layer using this new chemistry can be obtained at a low deposition temperature. Growth kinetics study indicates that these kinetic behaviors follow the Langmuir–Hinshelwood mechanism. Process optimization suggests that high-quality Al2O3 films with low carbon content and high refractive index, as well as the suppressed interfacial layer thickness of 0.2 nm, can be deposited at the substrate temperature of 300 °C and oxygen partial pressure of 1.6 Torr. On the basis of our investigation, it can be concluded that the MOCVD-derived Al2O3 films on Si grown by the new CVD chemistry show reasonable properties as promising candidates for high-k gate dielectrics.