Resist-Free Directed Self-Assembly Chemo-Epitaxy Approach for Line/Space Patterning

Abstract

This work reports a novel, simple, and resist-free chemo-epitaxy process permitting the directed self-assembly (DSA) of lamella polystyrene-block-polymethylmethacrylate (PS-b-PMMA) block copolymers (BCPs) on a 300 mm wafer. 193i lithography is used to manufacture topographical guiding silicon oxide line/space patterns. The critical dimension (CD) of the silicon oxide line obtained can be easily trimmed by means of wet or dry etching: it allows a good control of the CD that permits finely tuning the guideline and the background dimensions. The chemical pattern that permits the DSA of the BCP is formed by a polystyrene (PS) guide and brush layers obtained with the grafting of the neutral layer polystyrene-random-polymethylmethacrylate (PS-r-PMMA). Moreover, data regarding the line edge roughness (LER) and line width roughness (LWR) are discussed with reference to the literature and to the stringent requirements of semiconductor technology.

Controlled Anisotropic Wetting by Plasma Treatment for Directed Self-Assembly of High-χ Block Copolymers

“…Lamellae began to demonstrate a more satisfactorily straight configuration at γ PDMSB/SOC = 7.2 mN/m (pure oxygen treated surfaces, Figure B), but the best organization quality seems to appear for γ PS/SOC = 14.9 mN/m, and this outcome was achieved through modification of the substrate using HBr/O 2 treatment (Figure C). These results imply that the quality of the perpendicular lamellae directly correlates with the interfacial tension of the BCP domain that is wetting the SOC sidewalls, which is also observed in the literature. , Some might argue that the perpendicularity of the lines is affected by the commensurability between the BCP periodicity and the width of the trenches. However, as shown in Figure , within the corresponding normalized trench width of CHF 3 , HBr/O 2 , and O 2 plasma-treated substrates (i.e., 5 < w < 6), the corrugation of the curve is small, and hence, the commensurability effect is minimum.…”

“…These results imply that the quality of the perpendicular lamellae directly correlates with the interfacial tension of the BCP domain that is wetting the SOC sidewalls, which is also observed in the literature. 42,43 Some might argue that the perpendicularity of the lines is affected by the commensurability between the BCP periodicity and the width of the trenches. However, as shown in Figure 2, within the corresponding normalized trench width of CHF 3 , HBr/O 2 , and O 2 plasma-treated substrates (i.e., 5 < w < 6), the corrugation of the curve is small, and hence, the commensurability effect is minimum.…”

Directed Self-Assembly of Cylinder-Forming Block Copolymers Using Pillar Topographic Patterns

“…In DSA for nanoelectronics, a meaningful approach, along with line-space patterns [4,5], involves fabricating nanosized contact holes that serve as connection points for electrical signals across different layers or components in semiconductor devices, such as integrated circuits (ICs) [6][7][8][9]. Indeed, numerous recent studies demonstrate that DSA effectively complements extreme ultraviolet lithography (EUV), a premier method in the semiconductor industry [10][11][12].…”