Thermochemical study of new volatile palladium(II) and copper(II) β-ketohydrazonates for CVD application

The volatile palladium(II) and copper(II) {O,N}-coordinated bis-chelate complexes of a new type, Pd(dmht)2 and Cu(dmht)2, where dmht = 1,1,1-trifluoro-2-(2,2-dimethylhydrazone)pentan-4-onato, were synthesized, purified and identified by elemental analysis, IR and NMR spectroscopy and mass spectrometry. The thermal behavior of the complexes in the condensed phase was studied by TG-DTA and DSC methods. The temperature dependences of saturated vapor pressure were measured for Pd(dmht)2 and Cu(dmht)2 in the temperature ranges ΔT = (343–388) K (flow method) and ΔT = (321–390) K (flow and Knudsen effusion method), respectively. The ketohydrazonate complexes characterized by close enthalpy and entropy of melting and sublimation processes and the highest volatility among the related compounds. The new complexes were successfully used as precursors for metal-organic chemical vapor deposition of mono- and bimetallic thin films onto Si (100) substrates at the reducing atmosphere.