Aerosol Assisted Chemical Vapor Deposition of Gold and Nanocomposite Thin Films from Hydrogen Tetrachloroaurate(III)

Hydrogen tetrachloroaurate (HAuCl4) has been investigated as a precursor to gold films using aerosol assisted CVD. [HAuCl4] proved to be an excellent precursor to metallic gold, yielding films under a wide range of conditions with tunable optical properties. In addition, gold particles have been incorporated into several different transition metal oxide thin films (TiO2, WO3, and MoO3) using a single step process. The films were deposited onto silica glass using [Ti(OiPr)4], [W(CO)6], [Mo(CO)6], and [HAuCl4] as precursors, and acetone, methanol, and toluene as solvents. Substrate temperatures from 200 to 400 °C were used. XRD and XPS confirmed the presence of metallic gold and metal oxide within the films. The concentration of gold within the films could be varied widely; the Au:M (M = Ti, W, Mo) atomic ratio ranged from 0.1 to 1.9 depending on the initial precursor ratio. Films showed optical properties characteristic of gold nanocomposite materials:  surface plasmon resonance (SPR) absorption peaks and ...