Thin Solid Films, Vol.619, 265-272, 2016
Manganese half-sandwich complexes as metal-organic chemical vapor deposition precursors for manganese-based thin films
The synthesis of compounds [Mn(eta 5C5H4SiMe3)(CO)(3)] (1), [Mn(eta(C5H3)-C-5-1-SiMe3-3-Me)(CO)(3)] (2), [Mn(eta(C5H4Bu)-C-5-Bu-t)(CO)(3)] (3), [Mn(eta(C5Me5)-C-5)(CO)(3)] (4) and [Mn(eta(C5H7)-C-5)(CO)(3)] (5) and their potential use as metal-organic chemical vapor deposition (MOCVD) precursors for the deposition of manganese-based layers is reported. The thermal behavior of 15 was studied by thermogravimetry showing that these compounds evaporate in the temperature range of 363498 K depending on the cyclopentadienyl substituents and the type of pentadienyl used. Vapor pressure measurements indicate that all compounds possess vapor pressures between 60 and 630 Pa at 353 K. Compounds 15 could be successfully applied in manganese-based film deposition without activation steps prior to the MOCVD experiments. The as-deposited thin layers were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and X-ray powder diffraction. Under comparatively mild conditions, whereas 5 possesses the lowest deposition temperature (553 K), dense and conformal layers with growth rates up to 7.0 nm min(-1) (5) could be deposited. Metal carbonyls 1 and 2 featuring a SiMe3 group produced Si-containing manganese-based films. The as-deposited layers from 1, 2, 4 and 5 contain carbon impurities (58.9 mol-%), while the films from 3 are carbon-free. The layers from 1 and 2 consist of mainly manganese silicate and manganese oxide, whereas those obtained from 3 to 5 are composed of manganese oxides. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Metal-organic chemical vapor deposition;Manganese oxide;Thin films;Vapor pressure;X-ray photoelectron spectroscopy