Reaction of methylcyclopentadienyl manganese tricarbonyl on silicon oxide surfaces: Implications for thin film atomic layer depositions

Abstract

The thermal chemistry of methylcyclopentadienyl manganese tricarbonyl (MeCpMn(CO)3) on silicon oxide surfaces was characterized by a combination of analytical techniques, including gas chromatography/mass spectrometry (GC-MS), temperature-programmed desorption (TPD), infrared absorption spectroscopy, and X-ray photoelectron spectroscopy (XPS). The compound was found to be fairly stable, but to be able to dissociatively chemisorb on the surface via the loss of one or more carbonyl ligands followed by the oxidative addition of a surface silanol group. Further activation leads to the loss of the aromatic ligand, at temperatures above approximately 575 K. This takes place primarily via the addition of a hydrogen atom to the MeCp ligand to form methylcyclopentadiene, which is released to the gas phase, but a small competing channel starts at slightly lower temperatures that yields fulvene, and/or possibly benzene, after molecular rearrangement. The clean nature of the chemistry seen here for the methylcyclopentadienyl Mn complex makes it a good candidate as a precursor in the chemical deposition of metal thin films. However, the high stability and the high temperatures required for its decomposition do introduce some limitations.