Influence of the substrate on the morphological evolution of gold thin films during solid-state dewetting

Abstract The evolution of electron-beam evaporated Au thin films deposited on crystalline TiO 2 (c-TiO 2 ) and amorphous TiO 2 (a-TiO 2 ) as well as amorphous SiO 2 substrates are investigated. The kinetic of dewetting is clearly dependent on the type of substrate and is faster on TiO 2 substrates than on SiO 2 substrates. This difference can result from the difference in adhesion energy. Furthermore, the kinetic of dewetting is faster on a-TiO 2 than on c-TiO 2 , possibly due to the crystallization of TiO 2 during annealing induced dewetting process. The morphologies of dewetted Au films deposited on crystalline TiO 2 are characterized by branched holes. The XRD patterns of the Au films deposited on TiO 2 substrates constituted peaks from both metallic Au and anatase TiO 2 . The activation energy of Au films deposited on crystalline TiO 2 substrates was higher than that that of the films deposited on amorphous TiO 2 substrates.