Synchrotron radiation photoemission study of in situ manganese silicate formation on SiO2 for barrier layer applications

Synchrotron radiation photoelectron spectroscopy (SRPES) is used to investigate the in situ formation of ultra thin Mn silicate layers on SiO2, which has relevance for copper diffusion barrier layers in microelectronic devices. High temperature vacuum annealing of metallic Mn (similar to 1.5 nm) deposited on a 4 nm thermally grown SiO2 film results in the self limiting formation of a magnesium silicate layer, the stoichiometry of which is consistent with the formation of MnSiO3. Curve fitted Mn 3p SRPES spectra show no evidence for the presence of a manganese oxide phase at the Mn/SiO2 interface, in contrast to previous reports. (c) 2011 American Institute of Physics. [doi:10.1063/1.3567926]