Optical nanoscopy characterization of nanofilms

INERA Workshop 2016: Membrane and Liquid Crystal Nanostructures

Montgomery, P.C.^1 ; Chapuis, P.^2,3 ; Leong-Hoï, A.^1 ; Anstotz, F.^1 ; Rubin, A.^2 ; Baschnagel, J.^2 ; Gauthier, C.^2 ; Reiter, G.^3 ; McKenna, G.B.^4

Laboratoire des Sciences de l'Ingénieur, de l'Informatique et de l'Imagerie (ICube), Unistra-CNRS, 23 rue du Loess, Strasbourg

67037, France^1

Institut Charles Sadron (ICS), 23 rue du Loess, Strasbourg, France^2

Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, Freiburg

79104, Germany^3

Texas Tech University, Dept. of Chemical Eng., Box 43121, Lubbock

TX

79409-3121, United States^4

关键词: Film deformations;    Function of time;    Glass forming materials;    Interference microscopy;    Measurement cell;    Mechanical deformation;    Poly(vinyl acetate) (PVAc);    Viscoelastic properties;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/780/1/012003/pdf
DOI  :  10.1088/1742-6596/780/1/012003

来源: IOP

【 摘 要 】

Glass formation and glassy behavior remains an important field of study in condensed matter physics, with many aspects still little understood. The approach used in this work is to observe the changes in behavior of glass-forming materials at the nanometer scale by exploring the viscoelastic properties of ultrathin free-standing glassy polymer films. An experimental measurement cell based on the nanobubble inflation method is used, consisting of inflating a polymer film suspended over an array of 5 m diameter holes in a Si wafer. Measuring the deformation as a function of time as the material relaxes is used to determine the creep compliance. Both polystyrene (PS) and poly(vinyl acetate) (PVAc) films of a few tens of nm thickness prepared by spin-coating from solution have been studied. Interference microscopy is used to measure the deformation over several hours, which is challenging at the nanoscale due to mechanical deformations and drift. In this paper we present some of the first solutions developed to allow consistent measurements of film deformation using this novel interference nanoscopy technique. Future work will involve the measurements of creep compliance as a function of different film properties so as to be able to compare the results with theoretical predictions.