Molecular orbital studies of bonding characters of Al-N, Al-C, and N-C bonds in organometallic precursors to AlN thin films

Abstract

Electronic structures and properties of the organometallic precursors [Me2AlNHR](2) (R = Me, Pr-i, and Bu-t) have been calculated by the semiempirical (ASED-MO, MNDO, AM1 and PM3) methods. Optimized structures obtained from the MNDO, AM1, and PM3 calculations indicate that the N-C bond lengths are considerably affected by the change of the R groups bonded to nitrogen, but the bond lengths of the Al-N and Al-C bonds are little affected. This result is useful in explaining the experimental results for the elimination of the R groups bonded to nitrogen, and could serve as a guide in designing an optimum precursor for the AN thin film formation.