Modeling approaches for electron beam lithography

Koleva, Elena; Vutova, Katia; Asparuhova, B; Kostič, I.; Cvetkov, K; Gerasimov, V. F.

doi:10.1088/1742-6596/1089/1/012016

Cited by 4 publications

(3 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The undesired exposures were induced by the proximity effect of EBL, which is the deviation of electronic trajectories due to the scattering of electrons in the resist . The trajectories of various doses of electron beams were simulated using Monte Carlo software (Casino v2.51). ,− This simulation revealed that as the dose increased, the electron-beam trajectory diffused to a larger range, thereby initiating more reactions, which is consistent with the experimental results (Figure e). In Film B, the lines became blurrier with much lower contrast and line height (Figure d) than those in Film A (Figure c).…”

Section: Results and Discussionsupporting

confidence: 69%

Additive-Assisted Forming High-Quality Thin Films of Sn–Oxo Cluster for Nanopatterning

Zhao,

Huang,

et al. 2024

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Recently, metal−oxo clusters (MOCs) have attracted significant interest in fabricating nanoscale patterns in semiconductors via lithography. However, many MOCs are highly crystalline, making it difficult for them to form films and hindering subsequent nanopatterning processes. In this study, we developed a novel and simple method to enhance the filmforming ability of aromatic tetranuclear Sn−oxo clusters by adding additives. Theoretical calculations and Fourier-transform infrared (FTIR) analysis revealed the formation of intermolecular hydrogen bonds between the Sn−oxo clusters and additives, which induced a crystal−gel phase transition at −20 °C, thereby inhibiting the easy crystallization of the Sn− oxo clusters. High-quality and uniform thin films with surface roughness below 0.3 nm were prepared via spin coating. The obtained thin films exhibited good lithographic performance under deep ultraviolet (DUV), electron beam, and extreme-ultraviolet irradiation without a photo acid generator/photoinitiator, and 13-and 21 nm-wide line patterns were obtained on the films via electron-beam and extreme-ultraviolet lithographies. This study will pave the way for the further investigation of novel MOCs for advanced lithography and other thin-film applications.

show abstract

Section: Results and Discussionsupporting

confidence: 69%

Additive-Assisted Forming High-Quality Thin Films of Sn–Oxo Cluster for Nanopatterning

Zhao,

Huang,

et al. 2024

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…These intensities applied to develop metrology of thin film/substrate interactions in EBL. The literature suggests that these MC simulations provide an almost similar trajectory to that observed experimentally . Herein, the trajectory analysis was performed with the density of the resist using the monomer configuration of Terpolymer (C 25 H 34 O 3 ), and further, Ag-NPs (AgS 5 C 60 H 125 ) were added to analyze the effect.…”

Section: Experimental Sectionmentioning

confidence: 77%

“…The literature suggests that these MC simulations provide an almost similar trajectory to that observed experimentally. 48 Herein, the trajectory analysis was performed with the density of the resist using the monomer configuration of Terpolymer (C 25 H 34 O 3 ), and further, Ag-NPs (AgS 5 C 60 H 125 ) were added to analyze the effect. The e-beam spot was fixed to 0.5 nm, and the number of trajectories was kept constant to 5600.…”

Section: Methodsmentioning

confidence: 99%

Functionalized Ag Nanoparticles Embedded in Polymer Resists for High-Resolution Lithography

Moinuddin

Kumar

Yogesh

et al. 2020

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

Extending the resolution limit of next-generation lithography down to 15 nm or below requires the resist to attain small features, high irradiation sensitivity, and low line edge/width roughness. To meet this prerequisite, an increase of irradiation absorption in resists is an important strategy. A negative tone, deep ultraviolet, electron beam, and helium ion beam active resist formulation has been realized comprising a hydroxystyrene-based polymer tert-butyl 2-ethyl-6-(4-hydroxyphenyl)-4-phenylheptanoate (Terpolymer). Further, the resist performance was enhanced by doping of a microemulsion-based Ag nanoparticle (size distribution ∼2 nm) irradiation sensitizer. As a result, a tenfold decrease in the critical dose (E o ) was observed by increasing Ag nanoparticle contents from 0.1 to 1.0 wt %. The developed resist patterns exhibit significantly higher sensitivities and resolutions of 50 and 34.12 μC/cm 2 and ∼12 and ∼11 nm line patterns, respectively, for e-beam (E e ) and helium ion beam (E He ) irradiations. The line edge/width roughness of well-developed e-beam exposed patterns was found to be 1.5 ± 0.1/2.8 ± 0.3 nm, respectively. These e-beam/resist interactions were modeled by the Monte-Carlo trajectory, and the results were in line with the experimentally observed one. These simulations suggest the enhanced irradiation absorption inside the resist matrix with the addition of a high-electron-density Ag entity. These investigations reveal that one of the best ways to simultaneously improve the sensitivity and resolution of the resist is the optimum incorporation of higher-atomic-number nanoparticles in the polymeric matrix, which enhances the absorption cross section (σ) without altering the resist properties.

show abstract

Fabrication of sub-micrometer 3D structures for terahertz oscillators by electron beam gray-tone lithography

Bezhko

Suzuki

Iino

et al. 2022

Journal of Vacuum Science &Amp; Technology B

View full text Add to dashboard Cite

More and more novel applications are appearing in the almost-unexplored-up-to-recent-times frequency range of around 0.3–3 terahertz (THz), where sub-millimeter radio waves meet far-infrared optical waves. Resonant tunneling diodes (RTDs) are considered one of the promising compact and coherent room temperature signal sources for terahertz applications. In this work, the fabrication process and fabrication challenges for an RTD THz oscillator with a cylindrical resonant cavity are discussed. Successful fabrication of 3D metallic structures with a height of 2–5 μm and a feature size down to 0.5 μm was achieved by combining the traditional trilayer resist process with the dose-modulated (gray-tone) electron-beam (EB) lithography process. It was shown that two-step EB exposure could be used in thick (>2.4 μm) PMMA resist to achieve predictable and controllable fabrication of V-shaped metallic structures with lateral sizes down to 0.5 μm. Applicability of the described fabrication approach was proven by the measurement of oscillation characteristics for the fabricated RTD THz oscillators. Successful operation of the RTD oscillator devices confirms good electrical contact between the top contact of the RTD mesa structure and the RTD pillar structure as well as between the resonant cavity and antenna parts. The fabrication approach described in this work allowed us to eliminate parasitic capacitance formed around RTD mesa in the first fabrication trial and achieve a frequency increase of up to 200 GHz for RTD THz oscillators operating at frequencies 1.5–1.7 THz. The described fabrication approach may also be applicable for the fabrication of 3D metallic structures with a feature size less than 0.5 μm and a height more than 2 μm with EB energies above 50 keV.

show abstract

Modeling approaches for electron beam lithography

Cited by 4 publications

References 2 publications

Additive-Assisted Forming High-Quality Thin Films of Sn–Oxo Cluster for Nanopatterning

Additive-Assisted Forming High-Quality Thin Films of Sn–Oxo Cluster for Nanopatterning

Functionalized Ag Nanoparticles Embedded in Polymer Resists for High-Resolution Lithography

Fabrication of sub-micrometer 3D structures for terahertz oscillators by electron beam gray-tone lithography

Contact Info

Product

Resources

About