Poly(dimethylsiloxane-b-methyl methacrylate): A Promising Candidate for Sub-10 nm Patterning

Abstract

We report herein the modular synthesis and nanolithographic potential of poly­(dimethylsiloxane-block-methyl methacrylate) (PDMS-b-PMMA) with self-assembled domains approaching sub-10 nm periods. A straightforward and modular coupling strategy, optimized for low molecular weight diblocks and using copper-catalyzed azide–alkyne “click” cycloaddition, was employed to obtain a library of PDMS-b-PMMA and poly­(dimethylsiloxane-block-styrene) (PDMS-b-PS) diblock copolymers. Flory–Huggins interaction parameters, determined from small-angle X-ray scattering experiments, were high for PDMS-b-PMMA (χ ∼ 0.2 at 150 °C), suggesting this diblock copolymer system has promise for sub-10 nm lithographic applications when compared to the corresponding PDMS-b-PS diblock copolymers (χ ∼ 0.1 at 150 °C). Performance evaluation in thin film self-assembly experiments allowed domain periods as small as 12.1 nm to be obtained, which is among the smallest highly ordered nanoscale patterns reported hitherto for thermally annealed materials.

Directional Self‐Assembly of Fluorinated Star Block Polymer Thin Films Using Mixed Solvent Vapor Annealing

“…Thus, BPs with higher‐ χ have been developed with a goal of fabricating perpendicular domains with sub‐10 nm features . One straightforward approach is to increase the incompatibility between the two polymer blocks by changing the monomers' chemical structures while maintaining the linear BP molecular architecture . For example, Gopalan and coworkers reported sub‐5 nm features (i.e., equivalent to the half of L 0 ) with higher‐ χ BPs of poly(4‐ tert ‐butylstyrene)‐ block ‐poly(2‐vinylpyridine) (PtBuSt‐P2VP) in a parallel cylinder morphology, while Ryu and coworkers used fluorine‐containing PS‐ block ‐poly‐(2,2,2‐trifluoroethyl acrylate)s (PS‐PTFEA)s to achieve 5 nm features with higher χ‐ values and demonstrated the formation of perpendicular arrays with the help of a substrate modified by a neutral homopolymer mat .…”

Preparation and properties of 1,2‐polybutadiene grafting with poly(1,3‐butadiene)‐block‐(dimethylsiloxane)

“…The block copolymer of butadiene with octamethylcyclotetrasiloxane (PB‐b‐PDMS) initiated by n‐butyllithium carries not only residual double bonds but also siloxane groups. In this contribution, we described here a novel strategy to prepare graft‐modified 1,2‐PB by Mo‐based coordinative polymerization of PB‐b‐PDMS and butadiene.…”

Highly Ordered Structure Formation in RAFT-Synthesized PtBOS-b-P4VP Diblock Copolymers

“…Microphase separation is expected to be achieved easily in P t BOS‐ b ‐P4VP diblock copolymers since a random copolymer miscibility study showed that the ‐parameter of this combination was determined to be relatively high: 0.39 < 4VP, t BOS < 0.43 (even slightly higher in comparison to the PS‐ b ‐P4VP system, 0.30 < S,4VP ≤ 0.35). Such high χ systems are promising candidates for creating sub‐5 nm features in block copolymer systems that are otherwise impossible to achieve without additives …”