{"id":1938,"date":"2010-07-13T16:37:24","date_gmt":"2010-07-13T20:37:24","guid":{"rendered":"https:\/\/wpmu2.mit.local\/?p=1938"},"modified":"2010-07-13T16:37:24","modified_gmt":"2010-07-13T20:37:24","slug":"templated-self-assembly-of-block-copolymers-for-nanolithography","status":"publish","type":"post","link":"https:\/\/wpmu2.mit.local\/templated-self-assembly-of-block-copolymers-for-nanolithography\/","title":{"rendered":"Templated Self-assembly of Block Copolymers for Nanolithography"},"content":{"rendered":"
\"Figure<\/a>

Figure 1: (a and b) SEM images of highly organized and asymmetric complex cylindrical BCP patterns with an array of HSQ posts (brighter dots) prepared by electron-beam patterning. (a) Zig-zag pattern and (b) Meander structure with sharp bends. (c and d) Sub-10-nm-wide (a) PDMS pattern and their pattern transfer to (b) sub-10-nm tungsten nanowires.<\/p><\/div>\n

Self-organized macromolecular materials can provide an alternative pathway to conventional lithography for the fabrication of devices on the nanometer scale. In particular, the self-assembly of the microdomains of diblock copolymers within lithographically-defined templates to create patterns with long range-order has attracted considerable attention, with the advantages of cost-effectiveness, large-area coverage, and compatibility with pre-established top-down patterning technologies. Block copolymers consist of two covalently bound polymer chains of chemically distinct polymer materials. The chains can self-assemble to form small-scale domains whose size and geometry depend on the molecular weights of the two types of polymer and their interaction.<\/p>\n

\"Figure<\/a>

Figure 2: Square array of PFS dots from a thin film of PI-b-PS-b-PFS triblock terpolymer. PI and PS have been removed by O2 RIE.<\/p><\/div>\n

Previously, we showed that spherical morphology poly(styrene-b-dimethylsiloxane) (PS-PDMS) block copolymers, which have a large interaction parameter and a high etch-contrast between two blocks, can be templated using an array of nanoscale topographical elements that act as surrogates for the minority domains of the block copolymer [1<\/a>]<\/sup>. Recently, we showed that complex nanoscale patterns can be generated by combining the self-assembly of block-copolymer thin films with minimal top-down templating. A sparse array of nanoscale HSQ posts was used to accurately dictate the assembly of a cylindrical PS-PDMS diblock copolymer into a wide assortment of complex, unsymmetrical features, as shown in Figure 1(a) and (b) [2<\/a>]<\/sup>. To extend the feature sizes to the sub-10-nm range, we demonstrated the formation of highly ordered grating patterns with a line width of 8 nm and a period 17 nm from a self-assembled PS-PDMS diblock copolymer. Sub-10-nm-wide tungsten nanowires were fabricated from the self-assembled patterns using a reactive ion etching process, as shown in Figure 1(c) and (d).<\/p>\n

Beyond the rather limited morphologies of diblock copolymers, ABC triblock polymer thin films provide a diversity of new structures. For example, we obtained high-density nano-ring structures from a core-shell structured PS-PFS-P2VP triblock terpolymer after the selective removal of PS and P2VP [3<\/a>]<\/sup>. \u00a0Square arrays of dots can also be achieved from a self-assembled PI-PS-PFS triblock terpolymer, as shown in Figure 2 [4<\/a>]<\/sup>.<\/p>\n

\r\nReferences
  1. I. Bita, J.K.W. Yang, Y.S. Jung, C.A. Ross, E.L. Thomas, and K.K. Berggren, \u201cGraphoepitaxy of self-assembled block copolymers on two-dimensional periodic patterned templates,\u201d Science<\/em>, vol. 321, pp. 939-943, 2008. [↩<\/a>]<\/li>
  2. J.K.W. Yang, Y.S. Jung, J.-B. Chang, C.A. Ross, and K.K. Berggren, \u201cComplex self-assembled patterns using sparse commensurate templates with locally varying motifs,\u201d Nature Nanotechnology<\/em>, vol. 5, pp. 256-260, 2010. [↩<\/a>]<\/li>
  3. V.P. Chuang, C.A. Ross, J. Gwyther, and I. Manners, \u201cSelf-assembled nanoscale ring arrays from a polystyrene-b-polyferrocenylsilane-b-poly(2-vinylpyridine) triblock terpolymer thin film,\u201d Adv. Mater.<\/em> vol. 21, pp. 3789-3793, 2009. [↩<\/a>]<\/li>
  4. V.P. Chuang, J. Gwyther, R.A. Mickiewicz, I. Manner, and C.A. Ross, \u201cTemplated Self-Assembly of Square Symmetry Arrays from an ABC Triblock Terpolymer,\u201d Nano Lett.<\/em>, vol. 9, pp. 4364-4369, 2009. [↩<\/a>]<\/li><\/ol><\/div>","protected":false},"excerpt":{"rendered":"

    Self-organized macromolecular materials can provide an alternative pathway to conventional lithography for the fabrication of devices on the nanometer scale….<\/p>\n<\/div>","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[11],"tags":[64,41],"_links":{"self":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts\/1938"}],"collection":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/comments?post=1938"}],"version-history":[{"count":2,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts\/1938\/revisions"}],"predecessor-version":[{"id":1942,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts\/1938\/revisions\/1942"}],"wp:attachment":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/media?parent=1938"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/categories?post=1938"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/tags?post=1938"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}