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Ohlin, H., Benz, B., Romano, L. & Vogt, U. (2025). Lift-off free catalyst for metal assisted chemical etching of nanostructured silicon zone plates in vapour phase. Nano Express, 6(1), Article ID 015019.
Open this publication in new window or tab >>Lift-off free catalyst for metal assisted chemical etching of nanostructured silicon zone plates in vapour phase
2025 (English)In: Nano Express, E-ISSN 2632-959X, Vol. 6, no 1, article id 015019Article in journal (Refereed) Published
Abstract [en]

Metal-assisted chemical etching of silicon, especially in the vapour phase, is a highly promising technique for fabricating nanostructures with high aspect ratios. Here, a nanoscale pattern of x-ray zone plates written by electron beam lithography works as a mould for Pt electroplating on a Au seed layer to realise a nanostructured AuPt bilayer pattern on a silicon substrate. Our approach shows that the silicon etching induced by the electroplated catalyst occurs in a vapour of HF and oxygen, producing nanostructures with feature sizes as small as 10 nm, demonstrating that this catalyst synthesis method is suitable for vapour-based metal assisted chemical etching.

Place, publisher, year, edition, pages
IOP Publishing, 2025
Keywords
MACE, MacEtch, metall-assisted chemical etching, x-ray optics, zone plates
National Category
Other Physics Topics Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-362701 (URN)10.1088/2632-959X/adbd5b (DOI)001461107000001 ()2-s2.0-105002411423 (Scopus ID)
Note

QC 20250520

Available from: 2025-04-23 Created: 2025-04-23 Last updated: 2025-05-20Bibliographically approved
Åstrand, M., Vogt, U., Yang, R., Villanueva Perez, P., Li, T., Lyubomirskiy, M. & Kahnt, M. (2025). Multi-beam multi-slice X-ray ptychography. Scientific Reports, 15(1), Article ID 9273.
Open this publication in new window or tab >>Multi-beam multi-slice X-ray ptychography
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2025 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 15, no 1, article id 9273Article in journal (Refereed) Published
Abstract [en]

X-ray ptychography provides the highest resolution non-destructive imaging at synchrotron radiation facilities, and the efficiency of this method is crucial for coping with limited experimental time. Recent advancements in multi-beam ptychography have enabled larger fields of view, but spatial resolution for large 3D samples remains constrained by their thickness, requiring consideration of multiple scattering events. Although this challenge has been addressed using multi-slicing in conventional ptychography, the integration of multi-slicing with multi-beam ptychography has not yet been explored. Here we present the first successful combination of these two methods, enabling high-resolution imaging of nanofeatures at depths comparable to the lateral dimensions that can be addressed by state-of-the-art multi-beam ptychography. Our approach is robust, reproducible across different beamlines, and ready for broader application. It marks a significant advancement in the field, establishing a new foundation for high-resolution 3D imaging of larger, thicker samples.

Place, publisher, year, edition, pages
Springer Nature, 2025
Keywords
Multi-beam, Multi-slice, Ptychography
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-362002 (URN)10.1038/s41598-025-93757-0 (DOI)001447364200036 ()40102622 (PubMedID)2-s2.0-105000301304 (Scopus ID)
Note

Not duplicate with DiVA 1940472

QC 20250409

Available from: 2025-04-03 Created: 2025-04-03 Last updated: 2025-04-15Bibliographically approved
Roeper, S., Hussak, S.-A., Stachnik, K., Koziej, D., Åstrand, M., Vogt, U., . . . Schropp, A. (2025). Stereo hard X-ray ptychography. Optics Express, 33(11), 22755-22768
Open this publication in new window or tab >>Stereo hard X-ray ptychography
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2025 (English)In: Optics Express, E-ISSN 1094-4087, Vol. 33, no 11, p. 22755-22768Article in journal (Refereed) Published
Abstract [en]

Hard X-ray ptychography has strongly developed during the last decade, enabling one to visualize structural properties of materials at high spatial resolution. By combining it with multi-slicing or tomographic techniques, optically thick samples can be investigated in 3D. Nevertheless, the depth resolution in multi-slicing is often limited to several micrometers by the ptychographic optical system and a full laminographic or tomographic investigation may be hindered by experimental constraints of limited space or acquisition time. Here, we introduce a stereoscopic imaging system using two inclined nanofocused X-ray beams to illuminate a sample at varying angles at the same time. Similar to human vision, adding these stereoscopic views results in considerably improved in-depth resolution beyond the current limits of pure 2D imaging systems. This is especially promising for experimental applications requiring bulky sample environments.

Place, publisher, year, edition, pages
Optica Publishing Group, 2025
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-370561 (URN)10.1364/OE.559273 (DOI)001513705300003 ()40515256 (PubMedID)2-s2.0-105006770755 (Scopus ID)
Note

QC 20250929

Available from: 2025-09-29 Created: 2025-09-29 Last updated: 2025-09-29Bibliographically approved
Åstrand, M., Kahnt, M., Johansson, U. & Vogt, U. (2024). Adaptive multi-beam X-ray ptychography. Optics Express, 32(13), 22771-22780
Open this publication in new window or tab >>Adaptive multi-beam X-ray ptychography
2024 (English)In: Optics Express, E-ISSN 1094-4087, Vol. 32, no 13, p. 22771-22780Article in journal (Refereed) Published
Abstract [en]

Ptychography has evolved as an important method for nanoscale X-ray imaging with synchrotron radiation. Recently, it has been proposed to work with multiple beams in parallel. The main advantage of so-called multi-beam ptychography is that larger areas can be imaged much faster than with a conventional single beam scan. We introduce adaptive multi-beam ptychography performed with two Fresnel zone plates, placed one behind the other. In contrast to previous demonstrations of multi-beam ptychography, our optical scheme allows for adapting the spatial beam separation to the needs of the sample under investigation, relaxes thickness requirements on zone plates and is straightforward to implement. Moreover, it is simple to switch between single and multi-beam illumination during the same experiment. This opens the possibility of combining large and fast overview scans with detailed imaging of certain regions of interests.

Place, publisher, year, edition, pages
Optica Publishing Group, 2024
National Category
Atom and Molecular Physics and Optics Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-349936 (URN)10.1364/OE.509813 (DOI)001253476700011 ()39538756 (PubMedID)2-s2.0-85196731270 (Scopus ID)
Note

QC 20250325

Available from: 2024-07-03 Created: 2024-07-03 Last updated: 2025-03-25Bibliographically approved
Ohlin, H., Frisk, T., Sychugov, I. & Vogt, U. (2023). Comparing metal assisted chemical etching of N and P-type silicon nanostructures. Micro and Nano Engineering, 19, Article ID 100178.
Open this publication in new window or tab >>Comparing metal assisted chemical etching of N and P-type silicon nanostructures
2023 (English)In: Micro and Nano Engineering, E-ISSN 2590-0072, Vol. 19, article id 100178Article in journal (Refereed) Published
Abstract [en]

Metal assisted chemical etching is a promising method for fabricating high aspect ratio micro- and nanostructures in silicon. Previous results have suggested that P-type and N-type silicon etches with different degrees of anisotropy, questioning the use of P-type silicon for nanostructures. In this study, we compare processing X-ray zone plate nanostructures in N and P-type silicon through metal assisted chemical etching with a gold catalyst. Fabricated zone plates were cleaved and studied with a focus on resulting verticality, depth and porosity. Results show that for high aspect ratio nanostructures, both N and P-type silicon prove to be viable alternatives exhibiting different etch rates, but similarities regarding porosity and etch direction.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
MACE, Metal assisted chemical etching, N-type, Nanostructures, P-type, X-ray diffractive optics, Zone plate
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-330938 (URN)10.1016/j.mne.2023.100178 (DOI)001043751200001 ()2-s2.0-85151536658 (Scopus ID)
Note

QC 20230704

Available from: 2023-07-04 Created: 2023-07-04 Last updated: 2024-02-02Bibliographically approved
Kahnt, M., Selberg, J., Vogt, U., Åstrand, M., Björling, A., Kalbfleisch, S., . . . Johansson, U. (2023). Current capabilities of the imaging endstation at the NanoMAX beamline. In: AIP Conference Proceedings: . Paper presented at 15th International Conference on X-ray Microscopy, XRM 2022, Virtual, Online, Taiwan, Jun 19 2022 - Jun 24 2022. AIP Publishing, Article ID 040018.
Open this publication in new window or tab >>Current capabilities of the imaging endstation at the NanoMAX beamline
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2023 (English)In: AIP Conference Proceedings, AIP Publishing , 2023, article id 040018Conference paper, Published paper (Refereed)
Abstract [en]

The new imaging endstation of the NanoMAX beamline is being designed to complement the already existing diffraction endstation: measurements with smaller beams at lower photons energies, with higher stability, in vacuum and with sample cooling at the measurement position, optimized for X-ray fluorescence mapping and ptychographic imaging in two and three spatial dimensions. This comes at the cost of reduced flexibility and fewer degrees of freedom. We hereby present the results of the in-air commissioning of the main components for the new endstation and the data quality that has already been achieved.

Place, publisher, year, edition, pages
AIP Publishing, 2023
Series
AIP Conference Proceedings, ISSN 0094243X
National Category
Subatomic Physics Atom and Molecular Physics and Optics Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-340365 (URN)10.1063/5.0169244 (DOI)2-s2.0-85177551807 (Scopus ID)
Conference
15th International Conference on X-ray Microscopy, XRM 2022, Virtual, Online, Taiwan, Jun 19 2022 - Jun 24 2022
Note

QC 20231206

Available from: 2023-12-06 Created: 2023-12-06 Last updated: 2025-02-14Bibliographically approved
Lindblom, M., Patzauer, M., Vogt, U., Wilbur, S., Yazd, N. S., Tow, K. H., . . . Ebenhag, S. C. (2023). Flexible Liquid-Filled Scintillating Fibers for X-Ray Detection. In: 2023 IEEE SENSORS, SENSORS 2023 - Conference Proceedings: . Paper presented at 2023 IEEE SENSORS, SENSORS 2023, Vienna, Austria, Oct 29 2023 - Nov 1 2023. Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Flexible Liquid-Filled Scintillating Fibers for X-Ray Detection
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2023 (English)In: 2023 IEEE SENSORS, SENSORS 2023 - Conference Proceedings, Institute of Electrical and Electronics Engineers (IEEE) , 2023Conference paper, Published paper (Refereed)
Abstract [en]

We present the design and fabrication of flexible, liquid-filled scintillating fibers for X-ray detection made from silica fibers and silica capillaries. The scintillating fibers were characterized using ultraviolet light exposure and we also performed an experiment demonstrating X-ray detection.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2023
Keywords
liquid-filled fibers, scintillating fibers, X-ray detection
National Category
Biophysics
Identifiers
urn:nbn:se:kth:diva-341692 (URN)10.1109/SENSORS56945.2023.10325072 (DOI)001116741300222 ()2-s2.0-85179764298 (Scopus ID)
Conference
2023 IEEE SENSORS, SENSORS 2023, Vienna, Austria, Oct 29 2023 - Nov 1 2023
Note

Part of ISBN 9798350303872

QC 20231229

Available from: 2023-12-29 Created: 2023-12-29 Last updated: 2025-02-20Bibliographically approved
Åstrand, M., Kahnt, M., Johansson, U. & Vogt, U. (2023). Multi-beam ptychography with coded in-line Fresnel zone plates. In: X-Ray Nanoimaging: Instruments and Methods VI: . Paper presented at X-Ray Nanoimaging: Instruments and Methods VI 2023, San Diego, United States of America, Aug 23 2023 - Aug 24 2023. SPIE-Intl Soc Optical Eng, Article ID 1269807-1.
Open this publication in new window or tab >>Multi-beam ptychography with coded in-line Fresnel zone plates
2023 (English)In: X-Ray Nanoimaging: Instruments and Methods VI, SPIE-Intl Soc Optical Eng , 2023, article id 1269807-1Conference paper, Published paper (Refereed)
Abstract [en]

X-ray ptychography is often implemented for nanoimaging at synchrotron radiation sources and extensions are being developed to make experiments faster. This work is on multi-beam ptychography with Fresnel zone plates that have a small lateral separation, enabling the imaging of an extended field of view without increasing exposure time. Sectional zone inversion is implemented for coding respective probes and up to three Fresnel zone plates are successfully used in parallel. The speed-up achieved, compared to single beam ptychography, is linear with the number of probes. The combination of versatility of the fabrication process for the Fresnel zone plates and performance enhancement by scanning in multi-beam mode makes this an optimal solution for studying samples fast and obtaining enlarged fields of view.

Place, publisher, year, edition, pages
SPIE-Intl Soc Optical Eng, 2023
Keywords
Fresnel zone plate, multi-beam, ptychography
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-339976 (URN)10.1117/12.2676657 (DOI)2-s2.0-85176504471 (Scopus ID)
Conference
X-Ray Nanoimaging: Instruments and Methods VI 2023, San Diego, United States of America, Aug 23 2023 - Aug 24 2023
Note

Part of ISBN 9781510666108

QC 20231127

Available from: 2023-11-27 Created: 2023-11-27 Last updated: 2025-04-02Bibliographically approved
Ohlin, H., Frisk, T. & Vogt, U. (2023). Single Layer Lift-Off of CSAR62 for Dense Nanostructured Patterns. Micromachines, 14(4), Article ID 766.
Open this publication in new window or tab >>Single Layer Lift-Off of CSAR62 for Dense Nanostructured Patterns
2023 (English)In: Micromachines, E-ISSN 2072-666X, Vol. 14, no 4, article id 766Article in journal (Refereed) Published
Abstract [en]

Lift-off processing is a common method of pattern transfer for different nanofabrication applications. With the emergence of chemically amplified and semi-amplified resist systems, the possibilities for pattern definition via electron beam lithography has been widened. We report a reliable and simple lift-off process for dense nanostructured pattern in CSAR62. The pattern is defined in a single layer CSAR62 resist mask for gold nanostructures on silicon. The process offers a slimmed down pathway for pattern definition of dense nanostructures with varied feature size and an up to 10 nm thick gold layer. The resulting patterns from this process have been successfully used in metal assisted chemical etching applications.

Place, publisher, year, edition, pages
MDPI AG, 2023
Keywords
lift-off, single layer, electron beam lithography, CSAR62, X-ray diffractive optics, zone plate, nanostructures, nanofabrication
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-326871 (URN)10.3390/mi14040766 (DOI)000977289200001 ()37420999 (PubMedID)2-s2.0-85156107524 (Scopus ID)
Note

QC 20230515

Available from: 2023-05-15 Created: 2023-05-15 Last updated: 2024-02-02Bibliographically approved
Ohlin, H., Frisk, T., Åstrand, M. & Vogt, U. (2022). Miniaturized Sulfite-Based Gold Bath for Controlled Electroplating of Zone Plate Nanostructures. Micromachines, 13(3), Article ID 452.
Open this publication in new window or tab >>Miniaturized Sulfite-Based Gold Bath for Controlled Electroplating of Zone Plate Nanostructures
2022 (English)In: Micromachines, E-ISSN 2072-666X, Vol. 13, no 3, article id 452Article in journal (Refereed) Published
Abstract [en]

X-ray zone plates made from gold are common optical components used in X-ray imaging experiments. These nanostructures are normally fabricated using a combination of electron-beam lithography and gold electroplating with cyanide gold baths. In this study, we present a gold electroplating process in a miniaturized gold-suplphite bath. The miniaturization is enabled by on-chip reference plating areas with well defined sizes, offering a reliable way to control the height of the structures by carefully choosing the plating time at a given current density in accordance with a calibration curve. Fabricated gold zone plates were successfully used in X-ray imaging experiments with synchrotron radiation. Although gold electroplating of nanostructures is a well-established method, details about the actual process are often missing in the literature. Therefore, we think that our detailed descriptions and explanations will be helpful for other researchers that would like to fabricate similar structures.

Place, publisher, year, edition, pages
MDPI AG, 2022
Keywords
X-ray diffractive optics, zone plate, gold electroplating
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-311044 (URN)10.3390/mi13030452 (DOI)000774117300001 ()35334744 (PubMedID)2-s2.0-85127418184 (Scopus ID)
Note

QC 20220420

Available from: 2022-04-20 Created: 2022-04-20 Last updated: 2024-02-02Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-4394-0591

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