AVS 60th International Symposium and Exhibition
    Nanometer-scale Science and Technology Monday Sessions
       Session NS+BI+EM-MoM

Paper NS+BI+EM-MoM3
Predetermining Paths of Nanoscale Crack by Local Thermally Induced Strain Fields

Monday, October 28, 2013, 9:00 am, Room 203 B

Session: Nanophotonics and Plasmonics
Presenter: M.R. Cho, Seoul National University, Republic of Korea
Authors: M.R. Cho, Seoul National University, Republic of Korea
P.K. Kim, Seoul National University, Republic of Korea
Y.D. Park, Seoul National University, Republic of Korea
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We demonstrate well-defined path control of nanoscale cracks in SiO2 thin-films on Si substrate. When cracks are initiated their paths are confined in a predetermined track of arbitrary shape. The confinement of the crack paths is attributed to local thermally induced strain fields. We define the strain fields by utilizing the large differences between coefficients of linear thermal expansion between metallic thin-films and SiO2. On top of the substrate, a metallic strip of arbitrary shape is first predefined. Next, a layer of SiO2 is e-beam evaporated, followed by a thermal cycling. We then initiate the cracks by either a predetermined notch or by, more simply, a macro scratch far from the predefined track. Once the leading edge of the crack enters the predefined track, the crack, with width at the surface of SiO2 of ~50-200 nm, is laterally confined within a width > 2 µm, predefined path length in the millimeter range (or higher), and a minimal turn radius of curvature > 20 µm, and its path shape within the confined track is of nontrivial oscillatory. We present finite element analysis simulations as well as a model that explains and fits well the crack path shape within the track. We also discuss utilizing our results to realize bulk fabrication of nano-gap plasmonic device, nano-gap electrode and nano fluidic channel devices.