Study on Self-Formed Regular Copper and Aluminum Particles on the Surface of annealed Cu (Al)-Zr Alloyed Films

摘要

In this paper, regular Copper (Cu) and Aluminum (Al) particles and rods in submicron and nano-scale were prepared by annealing Cu-Zr, Cu-Al-Zr or Al-Zr alloyed thin films on polyimide substrates. XRD, FESEM, AFM and EDS were used to characterize their microstructures and composition. Results show that faceted Cu particles are very regular and pure Cu element. Furthermore, it was interesting to find that Cu rods might appear on the surface of the annealed Cu-Al-Zr composite thin films. Compared with Cu particles, faceted Al particles are slightly irregular. According to the experimental result and analysis, it were speculated that these Cu and Al particles are single crystals. The particle sizes are closely related to the content of Zr as well as annealing temperature. Mechanism was put forward to elucidate the formation of Cu and Al particles according to the morphological characterization and residual stress analysis. This work may provide a new approach to prepare metal particles and rods on the surface of films bonded on polyimide substrates.