Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film
Silicon-containing block copolymer thin films with high interaction parameter and etch contrast are ideal candidates to generate robust nanotemplates for advanced nanofabrication, but they typically form in-plane oriented microdomains as a result of the dissimilar surface energies of the blocks. Her...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
American Chemical Society (ACS)
2020
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| Online Access: | https://hdl.handle.net/1721.1/125669 |
| _version_ | 1826216406803283968 |
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| author | Lee, Sangho Cheng, Li-Chen Ross, Caroline A. |
| author2 | Massachusetts Institute of Technology. Department of Materials Science and Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Materials Science and Engineering Lee, Sangho Cheng, Li-Chen Ross, Caroline A. |
| author_sort | Lee, Sangho |
| collection | MIT |
| description | Silicon-containing block copolymer thin films with high interaction parameter and etch contrast are ideal candidates to generate robust nanotemplates for advanced nanofabrication, but they typically form in-plane oriented microdomains as a result of the dissimilar surface energies of the blocks. Here, we describe a two-step annealing method to produce vertically aligned lamellar structures in thin film of a silicon-containing rod-coil thermotropic liquid crystalline block copolymer. The rod-coil block copolymer with the volume fraction of the Si-containing block of 0.22 presents an asymmetrical lamellar structure in which the rod block forms a hexatic columnar nematic liquid crystalline phase. A solvent vapor annealing step first produces well-ordered in-plane cylinders of the Si-containing block, then a subsequent thermal annealing promotes the phase transition from in-plane cylinders to vertical lamellae. The pathways of the order-order transition were examined by microscopy and in situ using grazing incidence small-angle X-ray scattering and wide-angle X-ray scattering. |
| first_indexed | 2024-09-23T16:47:09Z |
| format | Article |
| id | mit-1721.1/125669 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T16:47:09Z |
| publishDate | 2020 |
| publisher | American Chemical Society (ACS) |
| record_format | dspace |
| spelling | mit-1721.1/1256692022-09-29T21:29:28Z Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film Lee, Sangho Cheng, Li-Chen Ross, Caroline A. Massachusetts Institute of Technology. Department of Materials Science and Engineering Silicon-containing block copolymer thin films with high interaction parameter and etch contrast are ideal candidates to generate robust nanotemplates for advanced nanofabrication, but they typically form in-plane oriented microdomains as a result of the dissimilar surface energies of the blocks. Here, we describe a two-step annealing method to produce vertically aligned lamellar structures in thin film of a silicon-containing rod-coil thermotropic liquid crystalline block copolymer. The rod-coil block copolymer with the volume fraction of the Si-containing block of 0.22 presents an asymmetrical lamellar structure in which the rod block forms a hexatic columnar nematic liquid crystalline phase. A solvent vapor annealing step first produces well-ordered in-plane cylinders of the Si-containing block, then a subsequent thermal annealing promotes the phase transition from in-plane cylinders to vertical lamellae. The pathways of the order-order transition were examined by microscopy and in situ using grazing incidence small-angle X-ray scattering and wide-angle X-ray scattering. National Science Foundation (U.S.) (Grant DMR-1606911) National Natural Science Foundation of China (Grant 51403132) National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (Award DMR-1419807) United States. Department of Energy. Office of Science Facilities (contract No. DE-SC0012704) 2020-06-04T15:10:39Z 2020-06-04T15:10:39Z 2020-03 2020-05-18T16:26:53Z Article http://purl.org/eprint/type/JournalArticle 1936-0851 https://hdl.handle.net/1721.1/125669 Shi, Ling-Ying et al. “Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film” ACS nano, vol.14 , no. 4, 2020, pp. 4289-4297 © 2020 The Author(s) en https://dx.doi.org/10.1021/acsnano.9b09702 ACS nano Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf American Chemical Society (ACS) ACS |
| spellingShingle | Lee, Sangho Cheng, Li-Chen Ross, Caroline A. Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film |
| title | Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film |
| title_full | Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film |
| title_fullStr | Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film |
| title_full_unstemmed | Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film |
| title_short | Vertical Lamellae Formed by Two-Step Annealing of a Rod-Coil Liquid Crystalline Block Copolymer Thin Film |
| title_sort | vertical lamellae formed by two step annealing of a rod coil liquid crystalline block copolymer thin film |
| url | https://hdl.handle.net/1721.1/125669 |
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