Deposition of metallic silver from versatile amidinate precursors for use in functional materials

Silver (Ag) amidinate metal organic decomposition precursors of the type: [Ag-2((ArN)(2)C(H))(2)] (Ar = 2,6-dimethylphenyl (1), 2,6-diethylphenyl (2) and 2,6-diisopropylphenyl (3)) have been used for the first time in the deposition of Ag films on glass with multiple functionalities with potential application in optical/biological sensors or for use in electronic circuitry. Precursors 1-3 were isolated from the reaction of silver acetate with the appropriate ligand in a 1:2 stoichiometry and were characterized by H-1 and C-13{H-1} NMR, thermal gravimetric analysis and single crystal X-ray diffraction for 2. Single-layer depositions at 200 degrees C on glass substrates via spin coating produced transparent (>90% transmittance) coatings, with well-defined Ag nanoparticles. Multi-layer depositions at 200 degrees C on glass had a metallic lustre and were found to be conductive (rho = 0.916-1.83 x 10(-6) omega m). All films were strongly adhered and displayed excellent coverage of the substrate. Ag films deposited from 1 to 3 were analysed by grazing incidence X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray analysis and scanning electron microscopy, with optical properties determined by UV-Vis spectroscopy.