1. Towards the MOCVD's paradise: Thermodynamics of phase transitions of new scandium precursors.
- Author
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Zherikova, Kseniya V., Makarenko, Alexander M., Sartakova, Anastasiya V., and Pishchur, Denis P.
- Subjects
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METAL organic chemical vapor deposition , *PHASE transitions , *SATURATION vapor pressure , *SCANDIUM , *CONDENSED matter - Abstract
[Display omitted] • Thermal properties of two new volatile fluorinated scandium(III) β-diketonates were studied. • Saturated vapor pressures were measured by the transpiration method. • TG-DTA and DSC analysis were carried out. • Standard molar enthalpies and entropies of sublimation, vaporization and fusion were derived. • Effect of fluorine introduction on thermal properties of the compounds was established. Scandium complexes with β-diketonate ligands are valuable precursors for the metal–organic chemical vapour deposition (MOCVD) of scandia based materials. The technology has been constantly developing and demanding novel precursors with accurately defined thermal properties, which could be used in MOCVD as well as related gas phase processes. Two new complexes with 1,1-difluoroacetylacetone (dfac) and 5,5,6,6,6-pentafluorohexane-2,4-dione (5Fac) have been synthesized, isolated, and characterized. The volatility and condensed phase behaviour including thermal stability and phase transitions of the obtained compounds have been studied; the saturated vapour pressures over crystalline Sc(dfac) 3 and liquid Sc(5Fac) 3 complexes have been measured. As a result, the standard molar thermodynamic characteristics of melting, sublimation, and vaporization processes have been calculated. Thermal properties of these compounds have been compared with literature data on scandium(III) β-diketonates already used as MOCVD precursor. These new compounds can be successfully used as precursors in the gas-phase deposition processes, and the set of obtained thermodynamic data can help in choosing the optimal deposition conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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