Extreme ultraviolet lithography reaches 5 nm resolution

Extreme ultraviolet (EUV) lithography is the leading lithography technique in CMOS mass production, moving towards the sub-10 nm half-pitch (HP) regime with the ongoing development of the next generation high-numerical aperture (high-NA) EUV scanners. Hitherto, EUV interference lithography (EUV-IL) utilizing transmission gratings has been a powerful patterning tool for the early development of EUV resists and related processes, playing a key role in exploring and pushing the boundaries of photon-based lithography. However, achieving pattering with HPs well below 10 nm using this method presents significant challenges. In response, our study introduces a novel EUV-IL setup that employs mirror-based technology and circumvents the limitations of diffraction efficiency towards the diffraction limit that is inherent in conventional grating-based approaches. We present line/space patterning of HSQ resist down to HP 5 nm using the standard EUV wavelength 13.5 nm, and the compatibility of the tool with shorter wavelengths beyond EUV. The mirror-based interference lithography tool paves the way towards the ultimate photon-based resolution at EUV wavelengths and beyond. This advancement is vital for scientific and industrial research, addressing the increasingly challenging needs of nanoscience and technology and future technology nodes of CMOS manufacturing in the few-nanometer HP regime

Poly(methyl methacrylate)-Based Nanofluidic Device for Rapid and Multiplexed Serological Antibody Detection of SARS-CoV‑2

The outbreak of SARS-CoV-2 has emphasized the value of point-of-care diagnostics, as well as reliable and cost-effective serological antibody tests, to monitor the viral spread and contain pandemics and endemics. Here, we present a three-dimensional (3D) nanofluidic device for rapid and multiplexed detection of viral antibodies. The device is made from poly­(methyl methacrylate) and contains 3D fluidic channels with nanoscale topography variations on the millimeter length scale, enabled by combining gray-scale e-beam lithography and nanoimprint lithography. It works with capillary pumps only and does not require a complex microfluidic setup and pumps, which hinder the widespread usage of micro- and nanofluidic devices. The device is designed to size dependently immobilize particles from a multiparticle mixture at predefined positions in nanochannels, resulting in distinct trapping lines. We show that it can be used as an on-chip fluorescence-linked immunosorbent assay for highly specific and sensitive multiplexed detection of serological antibodies against different viral proteins. Further test flexibility is demonstrated by on-bead color multiplexing for simultaneous detection of IgG and IgM antibodies in convalescent human serum. The particle sorting is further leveraged to enable concurrent detection of anti-spike (SARS-CoV-2) and anti-hemagglutinin (influenza A) antibodies. The device’s applications can be further extended to detect a large variety of diseases simultaneously in a reliable and straightforward manner

Poly(methyl methacrylate)-Based Nanofluidic Device for Rapid and Multiplexed Serological Antibody Detection of SARS-CoV‑2

The outbreak of SARS-CoV-2 has emphasized the value of point-of-care diagnostics, as well as reliable and cost-effective serological antibody tests, to monitor the viral spread and contain pandemics and endemics. Here, we present a three-dimensional (3D) nanofluidic device for rapid and multiplexed detection of viral antibodies. The device is made from poly­(methyl methacrylate) and contains 3D fluidic channels with nanoscale topography variations on the millimeter length scale, enabled by combining gray-scale e-beam lithography and nanoimprint lithography. It works with capillary pumps only and does not require a complex microfluidic setup and pumps, which hinder the widespread usage of micro- and nanofluidic devices. The device is designed to size dependently immobilize particles from a multiparticle mixture at predefined positions in nanochannels, resulting in distinct trapping lines. We show that it can be used as an on-chip fluorescence-linked immunosorbent assay for highly specific and sensitive multiplexed detection of serological antibodies against different viral proteins. Further test flexibility is demonstrated by on-bead color multiplexing for simultaneous detection of IgG and IgM antibodies in convalescent human serum. The particle sorting is further leveraged to enable concurrent detection of anti-spike (SARS-CoV-2) and anti-hemagglutinin (influenza A) antibodies. The device’s applications can be further extended to detect a large variety of diseases simultaneously in a reliable and straightforward manner

Poly(methyl methacrylate)-Based Nanofluidic Device for Rapid and Multiplexed Serological Antibody Detection of SARS-CoV‑2

The outbreak of SARS-CoV-2 has emphasized the value of point-of-care diagnostics, as well as reliable and cost-effective serological antibody tests, to monitor the viral spread and contain pandemics and endemics. Here, we present a three-dimensional (3D) nanofluidic device for rapid and multiplexed detection of viral antibodies. The device is made from poly­(methyl methacrylate) and contains 3D fluidic channels with nanoscale topography variations on the millimeter length scale, enabled by combining gray-scale e-beam lithography and nanoimprint lithography. It works with capillary pumps only and does not require a complex microfluidic setup and pumps, which hinder the widespread usage of micro- and nanofluidic devices. The device is designed to size dependently immobilize particles from a multiparticle mixture at predefined positions in nanochannels, resulting in distinct trapping lines. We show that it can be used as an on-chip fluorescence-linked immunosorbent assay for highly specific and sensitive multiplexed detection of serological antibodies against different viral proteins. Further test flexibility is demonstrated by on-bead color multiplexing for simultaneous detection of IgG and IgM antibodies in convalescent human serum. The particle sorting is further leveraged to enable concurrent detection of anti-spike (SARS-CoV-2) and anti-hemagglutinin (influenza A) antibodies. The device’s applications can be further extended to detect a large variety of diseases simultaneously in a reliable and straightforward manner

Understanding and Control of Polymer Distribution in Photoresists Using Liquid Chromatography for Enhanced Lithography Performance

The introduction of extreme ultraviolet lithography in high-volume manufacturing has once again ensured further progress in semiconductor technology. As we journey toward future technology nodes with smaller features, the quest for photoresists that meet these stringent specifications becomes increasingly challenging. Stochastic effects, such as the compositional dispersion of molecules in photoresists, have become a limiting factor in the lithography performance of photoresists. Here, we report on chromatographic techniques to separate random copolymers within photoresist materials according to chemical composition. We present a systematic study aimed at providing a fundamental understanding of how the molecular weight distribution and chemical composition of polymers included in photoresists influence lithography performance. Compared to other conventional methods, such as size exclusion chromatography, the approach in this study offers superior accuracy and resolution. It presents a promising approach to accurately identify and quantify the organic polymers within photoresists. Improved molecular dispersion of the polymers leads to an enhancement of the resist’s performance in EUV lithography. Our approach sets a standard in photoresist analysis and offers a viable approach to reduce stochastic effects, paving the way for photoresists with better performance for future technology nodes

Electrically Tunable Multicolored Filter Using Birefringent Plasmonic Resonators and Liquid Crystals

Dynamic tuning of color filters finds numerous applications including displays or image sensors. Plasmonic resonators are subwavelength nanostructures which can tailor the phase, polarization, and amplitude of the optical field, but they are limited in color vibrancy when used as filters. In this work, birefringence-induced colors of plasmonic resonators and a fast switching thin liquid crystal cell are combined in a multicolored electrically tunable filter. With this mechanism, the color gamut of the plasmonic surface and the liquid crystal cell is mutually enhanced in order to generate all primary additive and subtractive colors with high saturation as well as different tones of white. A single filter is able to cover more than 70% of the color gamut of standard RGB filters by applying a voltage ranging between 2 and 6.5 V. This spectral selectivity is added in transmission without any loss in the image resolution. The presented approach is foreseen to be implemented in a variety of devices including miniature sensors or smart-phone cameras to enhance the color information, ultraflat multispectral imagers, wearable or head-worn displays, as well as high resolution display panels

Electrically Tunable Multicolored Filter Using Birefringent Plasmonic Resonators and Liquid Crystals

Dynamic tuning of color filters finds numerous applications including displays or image sensors. Plasmonic resonators are subwavelength nanostructures which can tailor the phase, polarization, and amplitude of the optical field, but they are limited in color vibrancy when used as filters. In this work, birefringence-induced colors of plasmonic resonators and a fast switching thin liquid crystal cell are combined in a multicolored electrically tunable filter. With this mechanism, the color gamut of the plasmonic surface and the liquid crystal cell is mutually enhanced in order to generate all primary additive and subtractive colors with high saturation as well as different tones of white. A single filter is able to cover more than 70% of the color gamut of standard RGB filters by applying a voltage ranging between 2 and 6.5 V. This spectral selectivity is added in transmission without any loss in the image resolution. The presented approach is foreseen to be implemented in a variety of devices including miniature sensors or smart-phone cameras to enhance the color information, ultraflat multispectral imagers, wearable or head-worn displays, as well as high resolution display panels

Electrically Tunable Multicolored Filter Using Birefringent Plasmonic Resonators and Liquid Crystals

Dynamic tuning of color filters finds numerous applications including displays or image sensors. Plasmonic resonators are subwavelength nanostructures which can tailor the phase, polarization, and amplitude of the optical field, but they are limited in color vibrancy when used as filters. In this work, birefringence-induced colors of plasmonic resonators and a fast switching thin liquid crystal cell are combined in a multicolored electrically tunable filter. With this mechanism, the color gamut of the plasmonic surface and the liquid crystal cell is mutually enhanced in order to generate all primary additive and subtractive colors with high saturation as well as different tones of white. A single filter is able to cover more than 70% of the color gamut of standard RGB filters by applying a voltage ranging between 2 and 6.5 V. This spectral selectivity is added in transmission without any loss in the image resolution. The presented approach is foreseen to be implemented in a variety of devices including miniature sensors or smart-phone cameras to enhance the color information, ultraflat multispectral imagers, wearable or head-worn displays, as well as high resolution display panels

Electrically Tunable Multicolored Filter Using Birefringent Plasmonic Resonators and Liquid Crystals

Dynamic tuning of color filters finds numerous applications including displays or image sensors. Plasmonic resonators are subwavelength nanostructures which can tailor the phase, polarization, and amplitude of the optical field, but they are limited in color vibrancy when used as filters. In this work, birefringence-induced colors of plasmonic resonators and a fast switching thin liquid crystal cell are combined in a multicolored electrically tunable filter. With this mechanism, the color gamut of the plasmonic surface and the liquid crystal cell is mutually enhanced in order to generate all primary additive and subtractive colors with high saturation as well as different tones of white. A single filter is able to cover more than 70% of the color gamut of standard RGB filters by applying a voltage ranging between 2 and 6.5 V. This spectral selectivity is added in transmission without any loss in the image resolution. The presented approach is foreseen to be implemented in a variety of devices including miniature sensors or smart-phone cameras to enhance the color information, ultraflat multispectral imagers, wearable or head-worn displays, as well as high resolution display panels

The Extent of Platinum-Induced Hydrogen Spillover on Cerium Dioxide

Hydrogen spillover from metal nanoparticles to oxides is an essential process in hydrogenation catalysis and other applications such as hydrogen storage. It is important to understand how far this process is reaching over the surface of the oxide. Here, we present a combination of advanced sample fabrication of a model system and in situ X-ray photoelectron spectroscopy to disentangle local and far-reaching effects of hydrogen spillover in a platinum–ceria catalyst. At low temperatures (25–100 °C and 1 mbar H2) surface O–H formed by hydrogen spillover on the whole ceria surface extending microns away from the platinum, leading to a reduction of Ce4+ to Ce3+. This process and structures were strongly temperature dependent. At temperatures above 150 °C (at 1 mbar H2), O–H partially disappeared from the surface due to its decreasing thermodynamic stability. This resulted in a ceria reoxidation. Higher hydrogen pressures are likely to shift these transition temperatures upward due to the increasing chemical potential. The findings reveal that on a catalyst containing a structure capable to promote spillover, hydrogen can affect the whole catalyst surface and be involved in catalysis and restructuring