ADSORPTION OF ORDERED ZIRCONIUM PHOSPHONATE MULTILAYER FILMS ON SILICON AND GOLD SURFACES.

Multilayer films of zirconium 1,10-decanediylbis(phosphonate) have been prepared on silicon and gold substrates and characterized by ellipsometry, XPS, and electrochemical measurements. The deposition technique requires first covalent attachment or adsorption of a phosphonic acid anchoring agent. The functionalized substrates are exposed alternately to aqueous ZrOCl//2 and 1,10-decanediylbis(phosphonic acid) solutions to yield multilayer films. Ellipsometry shows an increase in film thickness, on Si, of 17 Angstrom/layer, which corresponds to the layer spacing in bulk Zr(O//3PC//1//0H//2//0PO//3). Variable take-off angle X-ray photoelectron spectra from four-layer films have attenuated Si peaks but strong Zr and P peaks when the detector is 70 degree off the surface normal, implying that the films on Si are continuous.