title: Pulsed transfer etching of PS-PDMS block copolymers self-assembled in 193 nm lithography stacks.
abstract: This work presents the graphoepitaxy of high-χ block copolymers (BCP) in standard industry-like lithography stacks and their transfer into the silicon substrate The process includes conventional 193 nm photolithography, directed self-assembly of polystyrene-block-polydimethylsiloxane (PS-b-PDMS) and pulsed plasma etching to transfer the obtained features into the substrate. PS-b-PDMS has a high Flory-Huggins interaction parameter (high-χ) and is capable of achieving sub-10 nm feature sizes. The photolithography stack is fabricated on 300 mm diameter silicon wafers and is composed of three layers: spin-on-carbon (SoC), silicon-containing anti-reflective coating (SiARC) and 193 nm photolithography resist. Sixty-nanometer-deep trenches are first patterned by plasma etching in the SiARC/SoC stack using the resist mask. The PS-b-PDMS is then spread on the substrate surface. Directed self-assembly (DSA) of the BCP is induced by a solvent vapor annealing process and PDMS cylinders parallel to the substrate surface are obtained. The surface chemistry based on SoC permits an efficient etching process into the underlying silicon substrate. The etching process is performed under dedicated pulsed plasma etching conditions. Fifteen nanometer half-pitch dense line/space features are obtained with a height up to 90 nm.
authors.affiliation: Université Grenoble Alpes , Laboratoire des Technologies de la Microélectronique , F-38000 Grenoble, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Girardot
authors.forename: Sophie
authors.initials: S
authors.lastname: Böhme
authors.forename: Sophie
authors.initials: S
authors.lastname: Archambault
authors.forename: Mathieu
authors.initials: M
authors.lastname: Salaün
authors.forename: Eddy
authors.initials: E
authors.lastname: Latu-Romain
authors.forename: Gilles
authors.initials: G
authors.lastname: Cunge
authors.forename: Olivier
authors.initials: O
authors.lastname: Joubert
authors.forename: Marc
authors.initials: M
authors.lastname: Zelsmann
keywords: PS-b-PDMS; directed self-assembly (DSA); graphoepitaxy; plasma etching; silicon nanostructures