Thin MnO and NiO films grown using atomic layer deposition from ethylcyclopentadienyl type of precursors

We report on the atomic layer deposition (ALD) of MnO and NiO thin films on Si(100) using Mn(EtCP)(2) [EtCp = ethylcyclopentadienyl, (C2H5)C5H4] and Ni(EtCp)(2) in the temperature range of 150-300 degrees C. H2O or O-3 is selected as oxygen source for the depositions. The growth temperature (T-g) and oxygen source impact on the structure, electronic density, and impurity concentration for the as-grown MnO and NiO films have been studied using X-ray reflectivity, (XRR), grazing incidence X-ray diffraction (GIXRD), and Fourier transform infrared (FTIR) spectroscopy. A steady growth rate of 0.024-0.025 nm/cycle for the films grown using Mn(EtCP)(2) and H2O was observed in the T-g range of 250-300 degrees C. FTIR does not show any carbon impurities in the MnO films grown with H2O. The films grown using Mn(EtCp)(2) and O-3 at 300 degrees C exhibit poor adhesion on Si(100). NiO films with low amounts of contaminants are achieved using O-3 and at a T-g of 250 degrees C or above. The growth rate, however, is very high for films deposited at T-g = 150 degrees C and decreases significantly in films deposited at higher temperatures. In addition, no film growth was observed for the Ni(EtCp)(2)/H2O process. The as-grown MnO and NiO films prepared using H2O and O-3 as oxidizer, is shown, by GIXRD a polycrystalline cubic structure. (C) 2008 Published by Elsevier B.V.