Stability Evaluation of Candidate Precursors for Chemical Vapor Deposition of Hafnium Diboride (HfB(2))

[Image: see text] Alternative candidate precursors to [Hf(BH(4))(4)] for low-temperature chemical vapor deposition of hafnium diboride (HfB(2)) films were identified using density functional theory simulations of molecules with the composition [Hf(BH(4))(2)L(2)], where L = −OH, −OMe, −O-t-Bu, −NH(2), −N=C=O, −N(Me)(2), and −N(CH(2))(5)NH(2) (1-piperidin-2-amine referred to as Pip2A). Disassociation energies (E(D)), potential energy surface (PES) scans, ionization potentials, and electron affinities were all calculated to identify the strength of the Hf–L bond and the potential reactivity of the candidate precursor. Ultimately, the low E(D) (2.07 eV) of the BH(4) ligand removal from the Hf atom in [Hf(BH(4))(4)] was partially attributed to an intermediate state where [Hf(BH(4))(3)(H)] and BH(3) is formed. Of the candidate precursors investigated, three exhibited a similar mechanism, but only −Pip2A had a PES scan that indicated binding competitive with [Hf(BH(4))(4)], making it a viable candidate for further study.