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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Directed self-assembly of cylinder-forming block copolymers: prepatterning effect on pattern quality and density
1Seagate Research Center, 1251 Waterfront Place, Pittsburgh, Pennsylvania 15222, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 6, 2009
Summary
This study introduces hydrogen silsesquioxane (HSQ) prepatterns for creating highly ordered block copolymer (BCP) cylinder arrays. HSQ enables superior BCP pattern quality and density compared to traditional methods.
Area of Science:
- Materials Science
- Nanotechnology
- Polymer Chemistry
Background:
- Block copolymer (BCP) self-assembly is crucial for fabricating nanostructures.
- Existing chemical prepatterning methods, like those using SiO(x), face limitations in pattern quality and density multiplication.
- Developing advanced prepatterning techniques is essential for achieving highly ordered BCP nanostructures.
Purpose of the Study:
- To demonstrate a novel prepatterning method using hydrogen silsesquioxane (HSQ) resist for fabricating dense, perpendicular block copolymer (BCP) cylinder arrays.
- To compare the effectiveness of HSQ-based prepatterns against conventional SiO(x)-based prepatterns.
- To investigate the impact of prepattern chemistry on BCP ordering and density multiplication.
Main Methods:
- Fabrication of prepatterns using hydrogen silsesquioxane (HSQ) resist.
- Creation of chemical prepatterns with exposed SiO(x) surfaces surrounded by a polystyrene (PS) brush matrix.
- Self-assembly of poly(styrene-b-dimethylsiloxane) (P(S-b-DMS)) block copolymers on the prepatterned substrates.
- Characterization of the resulting BCP cylinder arrays using electron microscopy and other relevant techniques.
- Comparison of graphoepitaxy and chemical prepatterning methods.
Main Results:
- HSQ-based prepatterns yielded significantly improved quality and density multiplication factors for perpendicular BCP cylinder arrays compared to SiO(x)-based prepatterns.
- HSQ prepatterns facilitated the formation of nearly perfectly ordered and well-registered arrays of P(S-b-DMS) cylinders.
- Simpler preparation procedures for HSQ prepatterns contributed to better BCP pattern induction.
- Graphoepitaxy on identical prepatterns achieved higher density multiplication than chemical prepatterning.
Conclusions:
- Hydrogen silsesquioxane (HSQ) resist offers a superior approach for chemical prepatterning in block copolymer lithography.
- The HSQ method enables the fabrication of high-density, well-ordered nanostructures essential for advanced material applications.
- This technique provides a pathway to overcome limitations of existing methods, paving the way for next-generation nanodevices.
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