Characterization of platnium/titanium interlayers by AFM

The surface microstructures of two samples of Pt/Ti interlayers, deposited onto SiO2/Si substrates by rf-magnetron sputtering, were characterized by a tomic force microscopy (AFM) and X-ray diffraction (XRD). The first sample of Pt/Ti interlayer was grown at a pressure 4.6mTorr and a substrate bias c urrent 2A. AFM studies of this interlayer show loosely packed, spherical po lycrystalline Pt grains with average size 50nm. Microcracks and porosity we re also present on this interlayer. The XRD studies of this sample indicate d low level of preferred (111) orientations. The Pb(Zr,Ti)O-3 (PZT) films g rown on this interlayer also had a low level of preferred (111) orientation . The second sample of Pt/Ti interlayer was grown under pressure 2.0mTorr a nd using a bias current 1A. The sample exhibits strong (111) peak in XRD. P hase-contrast imaging in the tapping mode AFM revealed elongated crystallit es of highly textured Pt grains. The grains are of size 6nm to 20nm in heig ht and 100nm across and their elongation appear to follow the direction of the bias current applied to the sample. The PZT films grown on this interla yer showed a preferred (111) texture.