Influence of proximity effects in electron-beam lithography on the optical properties of planar photonic-crystal waveguides

AbstractThe SIA roadmap predicts mass production of sub-100 nm resolution circuits by 2006. This not only imposes major constraints on next generation lithographic tools but also requires that new resists capable of accommodating such a high resolution be synthesized and developed concurrently. Except for ion beam lithography, DUV, X-ray, and in particular electron beam lithography suffer significantly from proximity effects, leading to severe degradation of resolution in classical resists. We report a new class of resists based on organic/inorganic nanocomposites having a structure that reduces the proximity effects. Synthetic routes are described for a ZEP520®nano-SiO2 resist where 47nm wide lines have been written with a 40 nm diameter, 20 keV electron beam at no sensitivity cost. Other resist systems based on polyhedral oligosilsesquioxane copolymerized with MMA, TBMA, MMA and a proprietary PAG are also presented. These nanocomposite resists suitable for DUV and electron beam lithography show enhancement in both contrast and RIE resistance in oxygen. Tentative mechanisms responsible for proximity effect reduction are also discussed.

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Corrections to proximity effects in electron beam lithography. I. Theory

Journal of Applied Physics ◽

10.1063/1.326423 ◽

1979 ◽

Vol 50 (6) ◽

pp. 4371-4377 ◽

Cited By ~ 90

Author(s):

Mihir Parikh

Keyword(s):

Electron Beam ◽

Electron Beam Lithography ◽

Proximity Effects

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Prototyping of three-dimensional photonic crystal structures using electron-beam lithography

MRS Proceedings ◽

10.1557/proc-846-dd12.3 ◽

2004 ◽

Vol 846 ◽

Cited By ~ 1

Author(s):

G. Subramania ◽

J. M. Rivera

Keyword(s):

Electron Beam ◽

Photonic Crystal ◽

Electron Beam Lithography ◽

Near Infrared ◽

Photonic Band Gap ◽

Three Dimensional ◽

Photonic Devices ◽

Layer By Layer ◽

Photonic Band Gap Structure ◽

Band Gap Structure

ABSTRACTWe demonstrate the fabrication of a three-dimensional woodpile photonic crystal in the near-infrared regime using a layer-by-layer approach involving electron-beam lithography and spin-on-glass planarization. Using this approach we have shown that we can make structures with lattice spacings as small as 550 nm with silicon as well as gold thus allowing for fabrication of photonic crystals with omnidirectional gap in the visible and near-IR. As a proof of concept we performed optical reflectivity and transmission measurements on a silicon structure which reveal peaks and valleys expected for a photonic band gap structure. The approach described here can be scaled down to smaller lattice constants (down to ∼400 nm) and can also be used with a variety of materials (dielectric and metallic) thus enabling rapid prototyping full three-dimensional photonic bandgap based photonic devices in the visible.

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Simulation of magneto-optical properties of magnetic photonic crystal waveguides

Journal of Nanophotonics ◽

10.1117/1.jnp.13.026002 ◽

2019 ◽

Vol 13 (02) ◽

pp. 1 ◽

Cited By ~ 2

Author(s):

Hamza Otmani ◽

Mahieddine Lahoubi ◽

Shengli Pu ◽

Mohamed Bouchemat ◽

Touraya Bouchemat ◽

...

Keyword(s):

Optical Properties ◽

Photonic Crystal ◽

Photonic Crystal Waveguides ◽

Magnetic Photonic Crystal

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Lithography with low-energy electrons

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112324 ◽

1984 ◽

Vol 42 ◽

pp. 468-471

Author(s):

T. H. Newman ◽

R. F. W. Pease ◽

K. J. Polasko ◽

Y. W. Yau

Keyword(s):

Electron Beam ◽

High Resolution ◽

Electron Beam Lithography ◽

Proximity Effects ◽

Low Energy ◽

Low Energy Electrons ◽

Circuit Fabrication ◽

Electron Range ◽

Exposure Process

Two prominent problems of electron beam lithography are slow throughput and proximity effects. The former arises from the serial nature of the exposure process; the current available in a beam of given resolution is limited by electron optical considerations and the resist sensitivity is limited by material considerations such that a dose of 1 μC/cm2 at 20 kV is required for the most sensitive resist and ten times that dose if high resolution is required.Proximity effects are caused by electrons scattered through lateral distances greater than the resolution of the pattern; a 20 keV electron in silicon has a range of about 3 μm whereas feature sizes are often less than 1 μm. Lowering the energy of the exposing electrons to, say, 2 keV would lower the electron range to less than 0.1 μm in silicon and thus effectively eliminate proximity effects as far as semiconductor circuit fabrication is concerned.

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Electron Beam Dose and PMMA Thickness Dependent Circularity and Diameter Analysis of Au Nanodots

Current Nanoscience ◽

10.2174/1573413714666181114104255 ◽

2019 ◽

Vol >15 (5) ◽

pp. 486-491 ◽

Cited By ~ 1

Author(s):

Furkan Kuruoğlu ◽

Özgür Yavuzçetin ◽

Ayşe Erol

Keyword(s):

Thin Films ◽

Optical Properties ◽

Electron Beam ◽

Electron Beam Lithography ◽

Thermal Evaporation ◽

Exposure Dose ◽

Homogeneous Distribution ◽

Electrical And Optical Properties ◽

Beam Dose ◽

Au Nanodots

Background: The electrical and optical properties of nanoparticle-based devices depend on the shape, dimension and uniformity of these particles. Methods: In this work, we fabricated ordered Au nanodots using electron beam lithography and thermal evaporation. Au nanodot diameter and circularity varied with a changed exposure dose and resist thickness. Electron beam dose ranged from 5 fC to 200 fC for single dot patterns. Commonly used PMMA thin films of thicknesses 60 nm and 100 nm coated samples were used for investigating the resist thickness dependency with varying dose exposure. Results: The analyses of patterns show that the diameter and circularity of the Au nanodots ranged from smaller to larger diameters and from lower to higher circularities with increasing dose and resist thickness. Conclusion: The distributions of the nanodot diameter began to show Gaussian behavior at larger electron doses. Besides, single circularity value became dominant up to the medium doses and then a homogeneous distribution was observed with the increasing dose.

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