title: Harnessing entropic and enthalpic contributions to create a negative tone chemically amplified molecular resist for high-resolution lithography.
abstract: Here we present a new resist design concept. By adding dilute cross-linkers to a chemically amplified molecular resist, we synergize entropic and enthalpic contributions to dissolution by harnessing both changes to molecular weight and changes in intermolecular bonding to create a system that outperforms resists that emphasize one contribution over the other. We study patterning performance, resist modulus, solubility kinetics and material redistribution as a function of cross-linker concentration. Cross-linking varies from dilute oligomerization to creating a highly networked system. The addition of small amounts of cross-linker improves resist performance by reducing material diffusion and redistribution during development and stiffening the features to avoid pattern collapse. The new dilute cross-linking system achieves the highest resolution of a sensitive molecular glass resist at 20 nm half-pitch and line-edge roughness (LER) of 4.3 nm and can inform new resist design towards patterned feature control at the molecular level.
authors.affiliation: Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (USA.
authors.forename: Prashant K
authors.initials: PK
authors.lastname: Kulshreshtha
authors.forename: Ken
authors.initials: K
authors.lastname: Maruyama
authors.forename: Sara
authors.initials: S
authors.lastname: Kiani
authors.forename: James
authors.initials: J
authors.lastname: Blackwell
authors.forename: Deirdre L
authors.initials: DL
authors.lastname: Olynick
authors.forename: Paul D
authors.initials: PD
authors.lastname: Ashby