SURFACE MORPHOLOGICAL MODIFICATION OF PT THIN-FILMS INDUCED BY GROWTHTEMPERATURE

Grazing-incidence x-ray reflectivity (GIXR), x-ray diffraction, and at omic-force microscopy (AFM) are used to characterize surface structure s of Pt thin films grown on ultrasmooth SiO2 substrates. The GIXR spec tra of the Pt thin films are found to be strongly dependent on the gro wth temperature. The surface roughness of the Pt thin films shows a mi nimum (1.21 nm) at the optimum temperature of 773 K, which is in good agreement with that obtained by the AFM measurements. The surface morp hology of the Pt thin film grown at 300 K is three dimensional and has mountainlike islands with smaller grain sizes of 10-20 nm. In contras t, the surface of the Pt thin film grown at 773 K is composed of ridge s, troughs, and fiat facets.