Development of Nanodomain and Fractal Morphologies in Solvent Annealed Block Copolymer Thin Films

We have systematically studied the thin film morphologies of asymmetric polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymer subjected to solvent vapors of varying selectivity for the constituent blocks. Upon a short treatment in neutral or PS-selective vapor, the film exhibited a highly ordered array of hexagonally packed, cylindrical microdomains. In the case of PEO selective vapor annealing, such ordered cylindrical microdomains were not obtained. instead, fractal patterns on the microscale were observed and their growth processes investigated. Furthermore, hierarchical structures could be obtained if the fractal pattern was exposed to neutral or PS selective vapor.

[1]  Paul Meakin,et al.  Fractals, scaling, and growth far from equilibrium , 1998 .

[2]  Zhiqun Lin,et al.  A Rapid Route to Arrays of Nanostructures in Thin Films , 2002 .

[3]  Qinglin Zhang,et al.  Observation of Inverted Phases in Poly(styrene-b-butadiene-b-styrene) Triblock Copolymer by Solvent-Induced Order−Disorder Phase Transition , 2000 .

[4]  A. Eisenberg,et al.  Control of Morphology through Polymer−Solvent Interactions in Crew-Cut Aggregates of Amphiphilic Block Copolymers , 1997 .

[5]  Yu Xuan,et al.  Solvent-induced microphase separation in diblock copolymer thin films with reversibly switchable morphology. , 2004, The Journal of chemical physics.

[6]  P. Alexandridis,et al.  Solvent-regulated ordering in block copolymers , 1999 .

[7]  G. Reiter,et al.  NANOMETER-SCALE SURFACE PATTERNS WITH LONG-RANGE ORDER CREATED BY CRYSTALLIZATION OF DIBLOCK COPOLYMERS , 1999 .

[8]  Yu Xuan,et al.  Morphology Development of Ultrathin Symmetric Diblock Copolymer Film via Solvent Vapor Treatment , 2004 .

[9]  Stephen Y. Chou,et al.  Macroscopic Orientation of Block Copolymer Cylinders in Single‐Layer Films by Shearing , 2004 .

[10]  T. Lodge,et al.  Phase Behavior of a Block Copolymer in Solvents of Varying Selectivity , 2000 .

[11]  Ian W. Hamley,et al.  The physics of block copolymers , 1998 .

[12]  Yanchun Han,et al.  Solvent Induced Sphere Development in Symmetric Diblock Copolymer Thin Films , 2005 .

[13]  H. Jaeger,et al.  Local Control of Microdomain Orientation in Diblock Copolymer Thin Films with Electric Fields , 1996, Science.

[14]  R. Saraf,et al.  Stability of Order in Solvent-Annealed Block Copolymer Thin Films , 2003 .

[15]  G. Fredrickson,et al.  Block copolymer thermodynamics: theory and experiment. , 1990, Annual review of physical chemistry.

[16]  T. Hashimoto,et al.  Morphology of block polymers near a free surface , 1985 .

[17]  A. Mayes,et al.  Block copolymer thin films : Physics and applications , 2001 .

[18]  Matthew Libera,et al.  Morphological Development in Solvent-Cast Polystyrene−Polybutadiene−Polystyrene (SBS) Triblock Copolymer Thin Films , 1998 .

[19]  S. Ludwigs,et al.  Self-assembly of functional nanostructures from ABC triblock copolymers , 2003, Nature materials.

[20]  Ting Xu,et al.  Highly Oriented and Ordered Arrays from Block Copolymers via Solvent Evaporation , 2004 .

[21]  M. Muthukumar,et al.  Mean-Field Theory for Diffusion-Limited Cluster Formation , 1983 .

[22]  Edwin L. Thomas,et al.  Microdomain patterns from directional eutectic solidification and epitaxy , 2000, Nature.

[23]  Craig J. Hawker,et al.  Block Copolymer Lithography: Merging “Bottom-Up” with “Top-Down” Processes , 2005 .

[24]  C. Hawker,et al.  Controlling Polymer-Surface Interactions with Random Copolymer Brushes , 1997, Science.

[25]  R. Segalman Patterning with block copolymer thin films , 2005 .

[26]  I. Hamley,et al.  Nanotechnology with soft materials. , 2003, Angewandte Chemie.

[27]  P. Nealey,et al.  Epitaxial self-assembly of block copolymers on lithographically defined nanopatterned substrates , 2003, Nature.

[28]  T. Lodge,et al.  Phase behavior of block copolymers in a neutral solvent , 2003 .

[29]  Kenji Fukunaga,et al.  Large-Scale Alignment of ABC Block Copolymer Microdomains via Solvent Vapor Treatment , 2000 .

[30]  V. Deline,et al.  Surface-induced orientation of symmetric, diblock copolymers: a secondary ion mass spectrometry study , 1989 .