Rhodium, palladium, iridium, and platinum are deposited by means of metal-organic (MO)CVD using metal beta-diketonates as precursors. Under some conditions, the microstructure of the deposited metals changes from compact to columnar. The potential causes of structural changes are investigated and a mechanism of contamination is proposed, based on the observation of growth singularities. Several Rh, Pd, Ir, and Pt coatings are analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution (HR)TEM, energy dispersive X-ray (EDX), and Gratan™ image filter (GIF) in order to observe composition, structure, and to identify the source of eventual structural changes.

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The thermal properties of some titanium precursors such as titanium (IV) isopropoxide (Ti[OPri]4 = TTIP); titanium(IV) ethoxide (Ti[OEt]4); titanium tetradimethylaminopropanol (Ti[DMAP]4) have been investigated by complex thermal analysis (thermogravimetric analysis etc.), mass-spectrometry, tensimetric methods (static and flow methods). The temperature dependences of saturated vapour pressure of titanium precursors have been obtained in a wide range of temperatures and thermodynamic parameters of vaporization processes have been calculated. Thermal decomposition of TTIP vapor has been investigated by high temperature mass spectrometry; temperature range and gaseous by-products were determined.

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In most high temperature applications, efficiency increases with service temperature of the component. Especially in combustion chambers, higher efficiency is translated into less propellant consumption and therefore a lower weight and a reduction of operational cost. In these components, the use of high performance coatings may simultaneously increase the service temperature and decrease its price. From the many available coating processes, Metal organic Chemical Vapour Deposition (MO-CVD) is one of the few capable of producing coatings of most precious metals in internal surfaces with intricate geometry. Nevertheless the microstructure control of the films is extremely complicated and characterised by the formation of dendrite structures. This morphology eliminates the coating efficiency, as it is not compact. EADS has had the chance to use the research infrastructure of the AMTT in Seibersdorf to characterise the coatings and determine how the transformation from the compact to the non-compact microstructure takes place. The understanding of this phenomenon should allow us to develop a process able to produce 100 % dense coatings independently of the coating thickness in an industrial scale.