Thermodynamic Study of Iridium(I) Complexes as a Basis for Chemical Gas-Phase Deposition Technology

Experimental data on the saturated vapor pressure and melting of dicarbonyl(hexafluoroacetylacetonato)iridium [Ir(CO)2(hfac)] were obtained. Thermodynamic characteristics of its melting and sublimation were calculated. A unified processing of p‒T dependences, the reduction of sublimation parameters to the standard temperature, and the thermodynamic modeling of the composition of condensed phases in the precursor‒gas‒ reagent system were carried out for three iridium(I) compounds: [Ir(CO)2(hfac)], [Ir(CO)2(acac)], and [Ir(cod)(hfac)] (acac– = acetylacetonate ion, cod = cyclooctadiene-1,3). The results form the basis for selection of a precursor and determination of the optimal deposition conditions for iridium(I)-based coatings.