[en] Decomposition of metal-organic precursors to Ba₂YCu₃O_7-δ films is difficult because of the high reaction temperature required to decompose the BaCO₃ intermediate. The recently proposed use of metal trifluoroacetate (TFA) solutions offers an alternative path to barium-containing superconducting films. The TFA salts decompose to the metal fluorides forming BaF₂, eliminating BaCO₃ from the system. Ultimate conversion to BYC, however, is shown not only to depend on hydrolysis of the BaF₂ at high temperatures, but also hydrolysis of copper trifluoracetate at low temperatures to prevent the volatilization of Cu(TFA)₂. These processes result in unique microstructural behavior which can be characterized by electron microscopy and Auger spectroscopy. Effects due to substrate interactions have been eliminated by use of a chemically inert substrate material, BaZrO₃