Metal bis-amidinate precursor is a promising candidate for atomic layer deposition (ALD) technology. The stability of these kinds of precursors can be characterized by calculating the migrating energy barrier and the reaction energy of β-group migration. Using density functional theory (DFT), the influence of nitrogen substituent of amidinate ligands to the stability of Co(II) bis-amidinate ALD precursors has been investigated. Calculation results show that the migration of β-H is significantly easier than that of β-Me, and the migrating sequence of β-group in different precursors is Co[ⁱPr-MeAMD]₂＜Co[^sBu-MeAMD]₂＜Co[^tBu-MeAMD]₂.

Key words: atomic layer deposition, bis-amidinate, transition state, density functional theory