Thin films of ZnO have been grown by low-pressure MOCVD using methylzinc isopropoxide, MeZn(OPi), and methylzinc tert-butoxide, MeZn(OBu*), in the absence of an added oxygen source. The films were grown on to glass substrates in the temperature range 250-400 "C with growth rates of between 0.2 and 4.4 pm h-'.

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Silver nanoparticles are being developed for applications in plasmonics, catalysts and analytical methods, amongst others. Herein, we demonstrate the growth of silver nanoparticles using an atomic layer deposition (ALD) process for the first time. The silver was deposited from pulses of the organometallic precursor (hfac)Ag(1,5-COD) ((hexafluoroacetylacetonato)silver(I)(1,5-cyclooctadiene)) dissolved in a 0.1 M toluene solution. Catalytic oxidative dehydrogenation of the silver was achieved using intermittent pulses of propanol. The effect of substrate temperature on the size and distribution of nanoparticles has been investigated over the temperature range 110-150 degrees C. Transmission electron microscopy reveals that the nanoparticles consist of face centred cubic, facetted silver crystallites. The localized surface plasmon modes of the nanoparticles have been investigated using electron energy loss spectroscopy mapping. The distributions of plasmons within the ALD nanoparticles are comparable to those grown by solution methods. Both dipolar and quadrupolar resonant modes are observed, which is consistent with previous discrete dipole approximation models. Energy loss mapping of a loss feature at 8.1 eV reveals that it correlates with the bulk or volume region of the silver nanoparticles investigated here.

HfO 2 and SrTiO 3 films were grown on silicon by liquid injection metal organic chemical vapour deposition. The microstructure and structure of the films were characterised by X-ray and electron diffraction, X-ray reflectometry, infrared spectroscopy, and microscopy techniques. In both cases, we emphasised the role of precursors in the resulting composition and microstructure of the films. Dense films of HfO 2 , either amorphous or crystalline depending on the deposition temperature, were synthesised using Hf(O t Bu) 2 (mmp) 2 precursor. Permittivity values of 14-19 were obtained, consistent with the monoclinic structure determined from X-ray diffraction. Optimised films exhibit breakdown field of6MVcm −1 and leakage current densities as low as 10 −8 Acm −2 at 1 V.Polycrystalline SrTiO 3 films were grown using either a mixture of precursors or a heterometallic precursor. The heterometallic precursor provides some advantages such as a lowering of the crystallisation temperature of the perovskite-type phase and a reduction of carbonate impurities at low temperatures. It also allows to keep the films composition constant over a wide temperature range (550-750 • C). The films are highly textured with [0 0 1] SrTiO 3 parallel to [0 0 1] Si . The permittivity depends strongly on the films thickness (ε r ∼ 30 for 10 nm and ε r ∼ 100 for 100 nm). An equivalent oxide thickness of 1.36 nm (for physical thickness of 15.0 nm) was obtained for optimised SrTiO 3 film, with a leakage current density of 10 −2 Acm −2 at 1 V.

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