Quantum chemical study on aluminum selective CVD reaction mechanism

Recently, aluminum (Al) selective chemical vapour deposition (CVD) on the silicon (Si) surface has received much attention as promising technology for ULSI metallization. The key issue is using a dimethyl aluminum hydride (DMAlH) over the Si surface terminated by hydrogen (H). In this quantum chemical study, we discuss the reaction mechanism. The reaction of Al-Al bond formation occurs prior to Al-S1 bond formation. The methyl group has an effect which suppresses the reactivity between Al and Si. Moreover, H, carrier gas increases the reactivity. These results are qualitatively in agreement with the experimental observations.