Exploiting volatile lead compounds as precursors for the atomic layer deposition of lead dioxide thin films

Lead dioxide thin films were grown by atomic layer deposition on Si(100) substrates. Lead diethyl-dithiocarbamate (Pb(dedtc)2), lead 2,2,6,6-tetramethyl-3,5-heptadione (Pb(thd)2) and tetraphenyl-lead (Ph4Pb) were used as lead precursors, and ozone as oxygen source. The depositions were carried out at 300–350 °C, 150–300 °C and 185–400 °C for Pb(dedtc)2, Pb(thd)2 and Ph4Pb, respectively. Attempts to use Pb(dedtc)2 as a lead-containing precursor for lead oxide thin films resulted in lead sulphate films, which reacted with the substrate and formed lead silicate during annealing. According to X-ray diffraction, films deposited from Pb(thd)2/O3 or from Ph4Pb/O3 were crystalline either orthorhombic or tetragonal lead dioxide. Surface morphology of the films were characterized by atomic force microscopy while time-of-flight elastic recoil detection analysis was used to analyse stoichiometry and possible impurities.