TY - JOUR

T1 - Towards the MOCVD's paradise: Thermodynamics of phase transitions of new scandium precursors

AU - Zherikova, Kseniya V.

AU - Makarenko, Alexander M.

AU - Sartakova, Anastasiya V.

AU - Pishchur, Denis P.

N1 - This work (Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences) was financially supported by the Russian Science Foundation and the Government of the Novosibirsk Region (grant number 22-23-20182).

PY - 2024/2

Y1 - 2024/2

N2 - 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.

AB - 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.

KW - Melting

KW - Scandium β-diketonate

KW - Standard molar enthalpy and entropy

KW - Sublimation

KW - Vaporization

KW - Vapour pressure

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85173438098&origin=inward&txGid=ca8eb52ad855e72d350f7d275d3456c5

UR - https://www.mendeley.com/catalogue/fde5541d-fb13-3749-a2ca-1b314d7dbb69/

U2 - 10.1016/j.jct.2023.107184

DO - 10.1016/j.jct.2023.107184

M3 - Article

VL - 189

JO - Journal of Chemical Thermodynamics

JF - Journal of Chemical Thermodynamics

SN - 0021-9614

M1 - 107184

ER -