A general method for controlled nanopatterning of oxide dots: a microphase separated block copolymer platform

We demonstrate a facile, generic method for the fabrication of highly dense long range hexagonally ordered various inorganic oxide nanodots on different substrates by using a microphase separated polystyrene-b-poly(ethylene oxide) (PS-b-PEO) block copolymer (BCP) thin film as a structural template. The method does not require complex co-ordination chemistry (between metal precursors and the polymer) and instead involves the simple, solution based chemistry applicable to a wide range of systems. A highly ordered PS-b-PEO thin film with perpendicularly oriented PEO cylinders is fabricated by solvent annealing over wafer scale. PEO cylinders are activated by ethanol to create a functional chemical pattern for nanodot development via spin coating and block selective metal ion inclusion. Subsequent UV/ozone treatment forms an ordered arrangement of oxide nanodots and removes the polymer components. The phase purity, crystallinity and thermal stability of these materials coupled to the ease of production may make them useful in technological applications. This method is particularly useful because the feature sizes can be tuned by changing the concentration of the precursors without changing the molecular weight and concentration of the block copolymer.

[1]  Eun Hye Kim,et al.  On the synergistic coupling properties of composite CdS/TiO2 nanoparticle arrays confined in nanopatterned hybrid thin films , 2010 .

[2]  W. Hinsberg,et al.  Lithographic Imaging Techniques for the Formation of Nanoscopic Features. , 1999, Chemical reviews.

[3]  Henryk Temkin,et al.  Low‐temperature photoluminescence from InGaAs/InP quantum wires and boxes , 1987 .

[4]  Dong Ha Kim,et al.  Fabrication and photocatalytic activities of morphology-controlled titania nanoobject arrays by block copolymer templates , 2007 .

[5]  Modelling effects of surface tension on surface topology in spin coatings for integrated optics and micromechanics , 2000 .

[6]  Margit Zacharias,et al.  Semiconductor nanowires: from self-organization to patterned growth. , 2006, Small.

[7]  C. Hawker,et al.  Block Copolymer Nanolithography: Translation of Molecular Level Control to Nanoscale Patterns , 2009, Advanced materials.

[8]  Mikael T. Björk,et al.  Integration of Colloidal Nanocrystals into Lithographically Patterned Devices , 2004 .

[9]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[10]  G. Whitesides,et al.  Unconventional Methods for Fabricating and Patterning Nanostructures. , 1999, Chemical reviews.

[11]  Leonidas E. Ocola,et al.  Enhanced Block Copolymer Lithography Using Sequential Infiltration Synthesis , 2011 .

[12]  M. F. Al-Kuhaili,et al.  Characterization of copper oxide thin films deposited by the thermal evaporation of cuprous oxide (Cu2O) , 2008 .

[13]  G. Sawatzky,et al.  In situ XPS analysis of various iron oxide films grown by NO2-assisted molecular-beam epitaxy , 1999 .

[14]  A. Alivisatos.  Semiconductor Clusters, Nanocrystals, and Quantum Dots , 1996, Science.

[15]  Soo-Jin Park,et al.  Fabrication of Highly Ordered Silicon Oxide Dots and Stripes from Block Copolymer Thin Films , 2008 .

[16]  Juan Peng,et al.  Development of Nanodomain and Fractal Morphologies in Solvent Annealed Block Copolymer Thin Films , 2007 .

[17]  M. Hillmyer,et al.  Nanoporous Polystyrene by Chemical Etching of Poly(ethylene oxide) from Ordered Block Copolymers , 2005 .

[18]  Timothy W. Collins,et al.  Cyclical "flipping" of morphology in block copolymer thin films. , 2011, ACS nano.

[19]  M. Morris,et al.  Self-assembled templates for the generation of arrays of 1-dimensional nanostructures: from molecules to devices. , 2010, Journal of colloid and interface science.

[20]  Harold G. Craighead,et al.  10‐nm resolution electron‐beam lithography , 1984 .

[21]  Andrew G. Glen,et al.  APPL , 2001 .

[22]  A. Kotani,et al.  Many-body effects in core-level spectroscopy of rare-earth compounds , 1988 .

[23]  C. Hawker,et al.  Mixed Lamellar Films: Evolution, Commensurability Effects, and Preferential Defect Formation , 2000 .

[24]  D. Goodman,et al.  Correlation of Relative X-ray Photoelectron Spectroscopy Shake-up Intensity with CuO Particle Size , 1999 .

[25]  Hongjun Gao,et al.  Large-Scale Fe3O4 Nanoparticles Soluble in Water Synthesized by a Facile Method , 2008 .

[26]  C. Chappert,et al.  Study of large area high density magnetic dot arrays fabricated using synchrotron radiation based x‐ray lithography , 1995 .

[27]  C. Stafford,et al.  Nanoscopic Templates from Oriented Block Copolymer Films , 2000 .

[28]  C. Tsvetanov,et al.  Intelligent networks based on poly(oxyethylene) , 1998 .

[29]  A. L. Shakhmin,et al.  Cellulose matrix as a nanoreactor for preparing nanoparticles of nickel and its oxides using hydrazine dihydrochloride as reductant , 2006 .

[30]  Miss A.O. Penney.  (b) , 1974, The New Yale Book of Quotations.

[31]  J. Sullivan,et al.  A study of the core level electrons in iron and its three oxides by means of X-ray photoelectron spectroscopy , 1983 .

[32]  Jongseung Yoon,et al.  Enabling nanotechnology with self assembled block copolymer patterns , 2003 .

[33]  Gongjun Yang,et al.  Fabrication of highly ordered microporous thin films by PS-b-PAA self-assembly and investigation of their tunable surface properties , 2008 .

[34]  J. Dominguez‐Vera,et al.  Apoferritin as a nanoreactor for preparing metallic nanoparticles , 2008 .

[35]  S. Darling,et al.  Nanoscopic Patterned Materials with Tunable Dimensions via Atomic Layer Deposition on Block Copolymers , 2010, Advanced materials.

[36]  J. Jung,et al.  Tunable magnetic arrangement of iron oxide nanoparticles in situ synthesized on the solid substrate from diblock copolymer micelles. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[37]  Thomas P. Russell,et al.  Highly Ordered Nanoporous Thin Films from Cleavable Polystyrene‐block‐poly(ethylene oxide) , 2007 .

[38]  H. Hansson,et al.  Nanometer patterning of InP using aerosol and plasma etching techniques , 1992 .

[39]  Christopher Harrison,et al.  Block copolymer lithography: Periodic arrays of ~1011 holes in 1 square centimeter , 1997 .