Speakers

Two-dimensional (2D) materials have emerged as promising platforms for the next generation of atomically thin devices, influencing diverse fields such as nanoelectronics, nanophotonics, quantum technologies, and energy conversion [1].
Here, we present a physical approach that enables the direct fabrication of few-layer transition metal dichalcogenide (TMD) films on large-area substrates [2]. Additionally, we demonstrate the use of thermal-Scanning Probe Microscopy (t-SPL) to create TMD circuits and nanoarchitectures with arbitrary geometries and deterministic positioning, thereby overcoming the constraints posed by the random alignment of small exfoliated flakes [3]. In these examples, we demonstrate that precise control over the lateral position and shape of TMD units is essential for tuning fine details of both the electronic properties as well as of light absorption in the flat-optic regime [4].
In a complementary way, we leverage t-SPL to manipulate and modify the electronic properties of individual crystalline TMD flakes using 3D grayscale lithography. By fabricating high-aspect-ratio faceted templates, we are able to conformally bend the TMD crystals, inducing a lateral strain modulation which is reflected in the contact potential difference assessed via Kelvin Probe Force Microscopy and by photoluminescence spectroscopy [under submission].

EUV interference lithography (EUV-IL) at the PSI has achieved high-resolution periodic patterning with record half-pitch resolution down to 5 nm enabled by transmission diffraction grating masks as well as a novel mirror-based setup. The tool produces high-contrast, focus-independent aerial images and has been a vital platform for the development of EUV materials. Recent advancements include resistless lithography, EUV patterning without photoresists. A new endstation planned to be commissioned by the end of 2025 will enhance thermal and mechanical stability as well as throughput, solidifying EUV-IL as a vital platform for advancing photoresists and techniques for next generation EUV lithography nodes.

Since the inventions of scanning tunneling microscope and atomic force microscope in 1980s, nanoscale imaging and manipulation capabilities have been greatly revolutionized. Particularly, scanning probe lithography has emerged as alternative subtractive/additive nanofabrication approaches, such as dip-pen nanolithography and thermal probe lithography.
At Westlake University, our group investigates fundamentals and applications of scanning probe technology. In this presentation, I will introduce our recent findings in scanning probe-based fabrication, in-situ characterization and manipulation of low-dimensional materials. Unique phenomena and functional nanodevices in electronics and photonics have been achieved for neuromorphic computing, such as resistive switching, ferroelectrics, logic-in-memory, and dynamic light-matter interactions.

2D semiconductors are extensively investigated for the next generation of nanoelectronics, as they hold the potential to replace silicon in transistors with sub-10 nm channel lengths. One of the emerging aspects being considered is strain engineering of 2D materials similar to the approach used in silicon-based transistors. We develop a new nanoengineering approach to induce deterministic strain in atomically thin MoS2 through topographic nanopatterning of the gate dielectric. Local and permanent bi-axial strain in MoS2 is achieved in a controllable way thanks to deterministic grayscale topographies made by thermal scanning probe lithography. Monolayer MoS2 FET under 1% tensile strain shows an 8-fold increase in on-state current and electron mobility of up to 185 cm²/Vs.

I will report on our latest developments on nanofabrication using thermal scanning probe lithography (t-SPL). The main focus of the presentation will be on the automation of the method. We use the nanometer-scale resolution of rapid AFM metrology to detect underlying devices, recover the local resist thickness, and perform nanometer-accurate overlay patterning. Automated tip-cleaning procedures are used to preserve high-resolution patterning over extended periods. Together with laser patterning, the tool is used to autonomously fabricate fin-type field effect transistors with sub-50 nm dimensions at chip scale. The achievement of fabricating complete devices solely relying on t-SPL is the next important step to establish t-SPL technology as a low-cost, low-damage, and high-resolution patterning method.

Two-dimensional (2D) materials exhibit rich optical and electronic properties that emerge from their reduced dimensionality and quantum confinement effects. By stacking various 2D crystals, van der Waals (vdW) heterostructures are created, providing a customizable platform to manipulate photons, electrons, and excitons in nanoscale devices. Thermal scanning-probe lithography (-tSPL) holds promise for patterning vdW heterostructures, offering rapid read–write capabilities, minimal sample damage, and grayscale surface topographies with nanometer precision. In this work, we exploit t-SPL to sculpt topographic landscapes in vdW heterostructures to tailor the behaviour of photons, electrons, and excitons in 2D materials for advanced quantum devices.

Low dimensional materials such as nanocarbons, colloidal quantum dots and van der Waals heterostructures have revealed their unique physical and chemical properties over the past decades. In this talk, I will mostly focus on our recent efforts in contacting graphene nanoribbons (GNRs). While the current fabrication process for such devices is not yet scalable, there is growing interest in developing automated processes that integrate material growth, control, contacting, and characterization. For carbon nanotube-based devices, we are developing experimental approaches towards scalable fabrication workflows, opening promising perspectives for applications in, for instance, sensing and quantum bits devices fabrication.

Direct write lithography has revolutionized nanofabrication, enabling rapid prototyping and the creation of complex micro- and nanostructures with unprecedented precision. At XRnanotech, we specialize in pushing the boundaries of resolution and efficiency, developing cutting-edge solutions for applications in X-ray optics, quantum technology, and nanoengineering. In this talk, I will present our latest advancements in ultra-high-resolution patterning, discuss key challenges in direct write lithography, and explore how next-generation techniques are shaping the future of nanotechnology. By combining innovation with industrial scalability, we aim to bridge the gap between research and commercial applications.

Organic thin-film transistors (TFTs) offer great potential for flexible electronics, where achieving high transit frequencies depends on both reducing device dimensions and minimizing contact resistance. While high-resolution lithography enables nanoscale scaling, our data showed that it also increases contact resistance, highlighting the need for a more optimized fabrication approach. Cross-sectional electron microscopy revealed that contact geometry, particularly the edge angle of the contacts, significantly influences contact resistance. By modifying metal deposition, we reduced contact resistance from 1.5 to 0.5 kΩcm. Further refinements in edge angle and fabrication methods will enhance the performance of high-frequency organic TFTs.

We fabricate tunnel junctions consisting of graphene and gold electrodes separated by hexagonal boron nitride (hBN) tunnel barriers. The corresponding IV curves feature a typical Fowler-Nordheim tunneling behavior. However, when a single layer of a transition metal dichalcogenide (TMD) is placed close by we observe resonant features in the IV curves. These resonant features match the TMD exciton energies. We thus observe optical modes in electrical transport measurements, without the injection of charge carriers into the TMDs.

Electrochemical nanopatterning with atomic force microscopy (AFM) enables precise fabrication of functional nanostructures via localized electrochemical reactions. We present two AFM-based approaches: bias-induced directed metal deposition and pulse-modulated local anodic oxidation (LAO). AFM tip-directed metal deposition utilizes cyclic charge modulation of the electrical double layer (EDL) to confine metal growth to nanoscale regions, demonstrating the potential for controlled additive nanofabrication. Meanwhile, the pulse-modulated LAO technique enables the flexible and high-precision fabrication of complex 3D oxide nanostructures, providing a versatile pathway for programmable functional nanostructures. These methods offer insights into electrochemical surface modification and a scalable strategy for next-generation (opto)electronic nanodevices.

Thermal Scanning Probe Lithography (t-SPL) enables high-precision nanofabrication with a single cantilever tip. Expanding to a multi-tip system, such as a 10-tip configuration, unlocks new possibilities for applications like meta-lens fabrication while introducing significant software challenges.
This talk examines the software adaptations required for parallelized t-SPL. It covers workflow comparisons between single and multi-tip systems, key changes across the technology stack, and strategies for maintaining compatibility with existing hardware and APIs.
Key topics include USB data handling, real-time constraints, UI adaptations for multi-tip operations and layout planning, and balancing performance with reliability in a precision-driven system.
The session highlights the software evolution behind multi-tip t-SPL and the technical considerations for implementing parallelized nanofabrication.

Probing emergent boundary modes and their non-local transport signatures has been an ongoing challenge for condensed matter physicists, and while progress has been made in quantum hall/spin hall systems, it remains elusive in superconductors. In this work we discuss a new method to fabricate high quality contacts to air-sensitive 2D superconductors, which reveals an anomalous non-local transport response in Fe(Te,Se) indicating the presence of edge states. We explore the critical details of how to properly characterize flakes, fabricate contacts, and measure this non-local transport response in superconductors.

Precise positioning of molecules and nanoparticles on surfaces is a key challenge in nanotechnology. One approach to addressing this is DNA origami: in this technique, a long single-strand DNA strand is folded into a desired shape using several shorter DNA strands. These structures allow molecular attachments at precise locations. This talk explores two methods for site-directed placement of DNA origami on surfaces: e-beam lithography, which offers high-resolution control for placing both 2D and 3D structures, and nanosphere
lithography, a cost-effective technique for patterning DNA origami on larger areas. These methods open new avenues for molecular assembly and nanofabrication.

In this talk, I will give an overview of some of the challenges of integrating the NanoFrazor into a thin film deposition system, from inert gas to ultra high vacuum without exposing to air. As an example, I will discuss the options for greyscale patterning of metasurfaces to impose strain on 2D materials and the challenges this could pose in characterisation with electron microscopy, Raman and scanning tunnelling microscopy. Finally, I will discuss possible routes for scaling up fabrication of such surfaces, with, for example nano-imprint lithography.

Phase change materials (PCMs) are raising interest in the nanophotonic domain, enabling reconfigurable optical functionalities. Sb2S3 is an emerging PCM being investigated for its low-loss optical properties, extending PCM applications into the visible wavelength range. In this presentation we will present the optical switching by laser illumination of Sb2S3 thin film and its reversible transition between amorphous and crystalline phase. We will discuss the power range required to trigger the phase transition and multiphysics simulations taking into account the thermal effect inside the material, which confirm the experimental measurements.

In this work, we demonstrate the capability of thermally nano-converting (TNC) individual nanostructures within a nanoscale array using the heated tip of the NanoFrazor. This approach enables precise, localised annealing with kinetics distinct from conventional bulk annealing. Leveraging thermal scanning probe lithography (t-SPL), we fabricate thin-film magnetic nano-island arrays and selectively apply TNC to specific regions. Our findings reveal that annealed islands exhibit a modified magnetic ground state and an enhanced magnetic saturation value, achieved without the inter-diffusion effects typically associated with bulk annealing. This work highlights the potential of TNC as a precise tool for tailoring nanoscale magnetic material properties.