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Berezkin AV, Jung F, Posselt D, Smilgies DM, Papadakis CM. Vertical vs Lateral Macrophase Separation in Thin Films of Block Copolymer Mixtures: Computer Simulations and GISAXS Experiments. ACS APPLIED MATERIALS & INTERFACES 2017; 9:31291-31301. [PMID: 28319360 DOI: 10.1021/acsami.6b16563] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mixtures of two diblock copolymers of very different lengths may feature both macro- and microphase separation; however, not much is known about the mechanisms of separation in diblock copolymer thin films. In the present work, we study thin films of mixtures of two compositionally symmetric block copolymers, both in the one-phase and in the two-phase state, combining coarse-grained molecular simulations (dissipative particle dynamics, DPD) with scattering experiments (grazing-incidence small-angle X-ray scattering, GISAXS). We reveal that the film thickness and selective adsorption of different blocks to the substrate control the distribution of macrophases within the film as well as the orientation of the lamellae therein. In thick films, the mixtures separate in the vertical direction into three layers: Two layers being rich in short copolymers are formed near the film interfaces, whereas a layer being rich in long copolymers is located in the film core. The lamellar orientation in the layers rich in short copolymers is dictated by the surface selectivity, and this orientation only weakly affects the vertical orientation of lamellae in the film core. This provides the opportunity to control the domain orientation in the copolymer films by mixing block copolymers with low-molecular additives instead of relying on a more complicated chemical modification of the substrate. In thinner films, a lateral phase separation appears.
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Affiliation(s)
- Anatoly V Berezkin
- Physik-Department, Physik weicher Materie, Technische Universität München , James-Franck-Strasse 1, 85748 Garching, Germany
| | - Florian Jung
- Physik-Department, Physik weicher Materie, Technische Universität München , James-Franck-Strasse 1, 85748 Garching, Germany
| | - Dorthe Posselt
- IMFUFA, Department of Science and Environment, Roskilde University , P. O. Box 260, 4000 Roskilde, Denmark
| | - Detlef M Smilgies
- Cornell High Energy Synchrotron Source (CHESS), Wilson Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Christine M Papadakis
- Physik-Department, Physik weicher Materie, Technische Universität München , James-Franck-Strasse 1, 85748 Garching, Germany
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Cummins C, Borah D, Rasappa S, Senthamaraikannan R, Simao C, Francone A, Kehagias N, Sotomayor-Torres CM, Morris MA. Self-Assembled Nanofeatures in Complex Three-Dimensional Topographies via Nanoimprint and Block Copolymer Lithography Methods. ACS OMEGA 2017; 2:4417-4423. [PMID: 31457733 PMCID: PMC6641768 DOI: 10.1021/acsomega.7b00781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 07/18/2017] [Indexed: 06/10/2023]
Abstract
Achieving ultrasmall dimensions of materials and retaining high throughput are critical fabrication considerations for nanotechnology use. This article demonstrates an integrated approach for developing isolated sub-20 nm silicon oxide features through combined "top-down" and "bottom-up" methods: nanoimprint lithography (NIL) and block copolymer (BCP) lithography. Although techniques like those demonstrated here have been developed for nanolithographic application in the microelectronics processing industry, similar approaches could be utilized for sensor, fluidic, and optical-based devices. Thus, this article centers on looking at the possibility of generating isolated silica structures on substrates. NIL was used to create intriguing three-dimensional (3-D) polyhedral oligomeric silsesquioxane (POSS) topographical arrays that guided and confined polystyrene-block-poly(dimethylsiloxane) (PS-b-PDMS) BCP nanofeatures in isolated regions. A cylinder forming PS-b-PDMS BCP system was successfully etched using a one-step etching process to create line-space arrays with a period of 35 nm in confined POSS arrays. We highlight large-area (>6 μm) coverage of line-space arrays in 3-D topographies that could potentially be utilized, for example, in nanofluidic systems. Aligned features for directed self-assembly application are also demonstrated. The high-density, confined silicon oxide nanofeatures in soft lithographic templates over macroscopic areas illustrate the advantages of integrating distinct lithographic methods for attaining discrete features in the deep nanoscale regime.
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Affiliation(s)
- Cian Cummins
- AMBER
Centre and CRANN, Trinity College Dublin, Dublin 2, Ireland
| | - Dipu Borah
- AMBER
Centre and CRANN, Trinity College Dublin, Dublin 2, Ireland
| | - Sozaraj Rasappa
- Optoelectronics
Research Center, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | | | - Claudia Simao
- Catalan
Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Achille Francone
- Catalan
Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Nikolaos Kehagias
- Catalan
Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Clivia M. Sotomayor-Torres
- Catalan
Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- ICREA, Pg. Lluís
Companys 23, 08010 Barcelona, Spain
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Choi J, Huh J, Carter KR, Russell TP. Directed Self-Assembly of Block Copolymer Thin Films Using Minimal Topographic Patterns. ACS NANO 2016; 10:7915-7925. [PMID: 27391372 DOI: 10.1021/acsnano.6b03857] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate that a minimal topographic pattern with a confinement depth (D) much less than the domain spacing of block copolymers (L0) can be used to achieve highly ordered hexagonal arrays or unidirectionally aligned line patterns over large areas. Cylinder-forming poly(styrene-b-ethylene oxide) (PS-b-PEO) thin films were prepared on a series of minimal single trench patterns with different widths (W) and D. Upon thermal annealing, hexagonal arrays of cylindrical microdomains propagated away from the edges of a single trench, providing insight into the minimum pitch (P) of the trench necessary to fully order hexagonal arrays. The confinement trench D of 0.30L0, the W in the range of 1.26L0 to 2.16L0, and the P as long as 18.84L0 were found to be effective for the generation of laterally ordered hexagonal arrays with the density amplification up by a factor of 17, within the minimally patterned trench surfaces of 100 μm by 100 μm. Furthermore, we produced line patterns of cylindrical microdomains by using solvent vapor annealing on the minimally patterned trench surfaces. However, highly aligned line patterns could be achieved only on the patterned surface with P = 5.75L0, W = 1.26L0, and D = 0.30L0 because the influence of the minimally patterned trench surface on the lateral ordering decreased as the P and W increase at the fixed D, resulting in poor ordering. These findings suggest that the minimal topographic pattern is more effective in guiding hexagonal arrays than in guiding line patterns.
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Affiliation(s)
- Jaewon Choi
- Department of Polymer Science and Engineering, University of Massachusetts Amherst , 120 Governors Drive, Amherst, Massachusetts 01003, United States
| | - June Huh
- Department of Chemical and Biological Engineering, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Kenneth R Carter
- Department of Polymer Science and Engineering, University of Massachusetts Amherst , 120 Governors Drive, Amherst, Massachusetts 01003, United States
| | - Thomas P Russell
- Department of Polymer Science and Engineering, University of Massachusetts Amherst , 120 Governors Drive, Amherst, Massachusetts 01003, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
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Berezkin AV, Papadakis CM, Potemkin II. Vertical Domain Orientation in Cylinder-Forming Diblock Copolymer Films upon Solvent Vapor Annealing. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b01771] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Anatoly V. Berezkin
- Physik-Department,
Physik weicher Materie, Technische Universität München, James-Franck-Str.
1, 85748 Garching, Germany
| | - Christine M. Papadakis
- Physik-Department,
Physik weicher Materie, Technische Universität München, James-Franck-Str.
1, 85748 Garching, Germany
| | - Igor I. Potemkin
- Physics
Department, Lomonosov Moscow State University, Moscow 119991, Russian Federation
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Xiao S, Yang X, Steiner P, Hsu Y, Lee K, Wago K, Kuo D. Servo-integrated patterned media by hybrid directed self-assembly. ACS NANO 2014; 8:11854-11859. [PMID: 25380228 DOI: 10.1021/nn505630t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A hybrid directed self-assembly approach is developed to fabricate unprecedented servo-integrated bit-patterned media templates, by combining sphere-forming block copolymers with 5 teradot/in.(2) resolution capability, nanoimprint and optical lithography with overlay control. Nanoimprint generates prepatterns with different dimensions in the data field and servo field, respectively, and optical lithography controls the selective self-assembly process in either field. Two distinct directed self-assembly techniques, low-topography graphoepitaxy and high-topography graphoepitaxy, are elegantly integrated to create bit-patterned templates with flexible embedded servo information. Spinstand magnetic test at 1 teradot/in.(2) shows a low bit error rate of 10(-2.43), indicating fully functioning bit-patterned media and great potential of this approach for fabricating future ultra-high-density magnetic storage media.
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Affiliation(s)
- Shuaigang Xiao
- Media Research Center, Seagate Technology , 47010 Kato Road, Fremont, California 94538, United States
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