1Department of Physics, Huazhong University of Science and Technology, Wuhan 430074 2Department of Physics and Institute of Nano Science and Technology, Hong Kong University of Science and Technology, Hong Kong 3Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
Spontaneous Hillock Growth on Indium Film Surface
WEI He-Lin1;ZHANG Xi-Xiang2;HUANG Han-Chen3
1Department of Physics, Huazhong University of Science and Technology, Wuhan 430074 2Department of Physics and Institute of Nano Science and Technology, Hong Kong University of Science and Technology, Hong Kong 3Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
Uniformly distributed indium hillocks are grown on silicon substrates by dc magnetron sputtering. The morphologies and the microstructures have been investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction (XRD). From the TEM and SEM images, we find that, at the earlier stage, the grain coalescent process dominates. This coalescent process induces a larger compressive stress. We believe that the drive force for hillock growth comes from this compressive stress. Under this compressive stress, the grain locating in the middle of several grains are extruded from these grains, and then a hillock forms with the increasing deposition time. For low melting point and high diffusion coefficient metal, such as bismuth and indium, this spontaneous-hillock growth mechanism can be used to fabricate well aligned nanostructures.
2006, Vol. 23 
