Growth of WOx from Tungsten(VI) Oxo-Fluoroalkoxide Complexes with Partially Fluorinated β-Diketonate/β-Ketoesterate Ligands: Comparison of Chemical Vapor Deposition to Aerosol-Assisted CVD

Tungsten(VI) oxo complexes of the type WO(OR)₃L [R = C(CH₃)₂CF₃, C(CF₃)₂CH₃, CH(CF₃)₂, L = hexafluoroacetylacetonate (hfac), ethyl trifluoroacetoacetonate (etfac), acetylacetonate (acac)] bearing partially fluorinated alkoxide and/or chelating ligands were synthesized. Thermal decomposition behavior and mass spectrometry (MS) fragmentation patterns of selected examples were studied. The thermolysis products of WO(OC(CF₃)₂CH₃)₃(hfac) were characterized by nuclear magnetic resonance and gas chromatography-MS. Studies of the sublimation behavior of the complexes demonstrated that their volatility depends on the degree of fluorination. Comparative studies of the deposition of tungsten oxide by chemical vapor deposition (CVD) and aerosol-assisted CVD were carried out using WO(OC(CF₃)₂CH₃)₃(hfac) as a single-source precursor. WO_x materials were successfully deposited by both deposition methods, but the deposits differed in morphology, structure, and crystallinity.