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We propose two-layered thin film architecture and its fabrication method based on industry-compatible processing techniques. The strategic approach includes a combination of polymer embedded quantum dots (QD) film coated with an additional oxide layer. This assembly offers an increased photo-thermal stability and provides a simple architecture for various luminescent thin film based applications. Quantum dots, a nanometer sized crystallites, offering high intensity photoluminescence are a promising material for absorbing and converting light energy applications. However, they are very sensitive to the environmental conditions and their degradation presents major challenges. Many of the most promising technological applications of luminescence require thin films. Film deposition technology is well-established in industry with a number of different techniques used for the manufacturing of both polymeric and inorganic thin films. From industrial point of view, the fabrication of QD-polymer composites and their high quality thin films is extremely relevant and despite many advantages, this development has been inhibited by incompatibility of QDs with polymeric environments. We addressed these issues and developed a system that presents many opportunities for possible industrial applications of QD-based materials. We proposed a straight forward solution for incorporation of colloidal QDs into polymer without any modifications to the synthetic route or luminescent properties deterioration, directly providing a simple and cost-reduced formulation that can be employed in thin film fabrication. Further studies focused on the evaluation of the QD-polymer thin film long-term optical efficiency, ultimately leading to the introduction of an additional protective coating. The oxide layer, acting as a barrier, was processed via plasma assisted ALD technique directly onto QD-polymer film, which allows to maintain the continuity for the large scale processing. An extensive study was undertaken where the degradation trends of both, the non-coated and oxide coated QD-polymer film samples, were assessed under accelerated aging conditions, including high intensity illumination (150 mW/cm2), an increased temperature (85C) and humidity (85%). Highlighting the impact of each parameter, the evaluation was performed based on the luminescence quantum efficiency deterioration as a function of exposure time. The analysis showed that, even under the most demanding conditions, samples with protective layer have retained their photoluminescence stability at 80% of the original level over the period of 300h, whereas the unprotected ones, have dropped to 30% after 75h. The study indicated that the introduction of a dual encapsulation system for QDs has significantly extended their operational lifetime. The polymer material has a two-fold functionality providing both, mechanical and chemical stability to the QDs, as well as the role of the matrix material, whereas oxide layer acts as a direct barrier against external environment.

Bimetallic nanocatalysts are key enablers of current chemical technologies, including car exhaust converters and fuel cells, and play a crucial role in industry to promote a wide range of chemical reactions. However, owing to significant characterization challenges, insights in the dynamic phenomena that shape and change the working state of the catalyst await further refinement. Herein, we discuss the atomic‐scale processes leading to mono‐ and bimetallic nanoparticle formation and highlight the dynamics and kinetics of lifetime changes in bimetallic catalysts with showcase examples for Pt‐based systems. We discuss how in situ and operando X‐ray spectroscopy, scattering, and diffraction can be used as a complementary toolbox to interrogate the working principles of today's and tomorrow's bimetallic nanocatalysts.

In next-generation EUV imaging for foundry N5 dimensions and beyond, inherent pitch- and orientation-dependent effects on wafer level will consume a significant part of the lithography budget using the current Ta-based mask. Mask absorber optimization can mitigate these so-called mask 3D effects. Thin metal absorbers like Ni and Co have been experimentally investigated due to their high EUV absorption, but they pose challenges on the current technology of subtractive mask patterning [1]. A simulation study of attenuated EUV phase shift masks has identified through multiobjective optimization superior imaging solutions for specific use cases and illumination conditions [2]. Evaluating novel EUV mask absorbers evolves on two levels, demonstrating (1) improvements from lithographic perspective and (2) compatibility with the full mask supply chain including material deposition, absorber patterning, scanner environment compatibility and mask lifetime. On the lithographic level, we have identified regions based on the material optical properties and their gain in imaging performance compared to the reference Ta-based absorber. Within each improvement region we engineered mask absorber materials to achieve both the required imaging capabilities, as well as the technical requirements for an EUV mask absorber. We discuss the material development of Te-based alloys and Ag-based layered structures, because of their high EUV extinction. For the attenuated phase shift materials, we start from a Ru-base material, due to its low refractive index, and construct Ru-alloys. On the experimental level, we examined our novel mask absorber materials against an initial mask absorber requirement list using an experimental test flow. Candidate materials are evaluated on film morphology and stability through thermal, hydrogen, EUV loading, and chemical cleaning, for their EUV optical constants by EUV reflectometry, as well as preliminary for selective dry etch. The careful mask absorber evaluation, combining imaging simulations and experimental material tests, allowed us to narrow down to promising combinations for novel EUV mask absorbers.

Published under an ACS AuthorChoice license Novel coating materials are constantly needed for current and future applications in the area of microelectronics, biocompatible materials, and energy-related devices. Molecular layer deposition (MLD) is answering this cry and is an increasingly important coating method for organic and hybrid organic-inorganic thin films. In this study, we have focused on hybrid inorganic-organic coatings, based on trimethylaluminum, monofunctional aromatic precursors, and ring-opening reactions with ozone. We present the MLD processes, where the films are produced with trimethylaluminum, one of the three aromatic precursors (phenol, 3-(trifluoromethyl) phenol, and 2-fluoro-4-(trifluoromethyl)benzaldehyde), ozone, and the fourth precursor, hydrogen peroxide. According to the in situ Fourier-transform infrared spectroscopy measurements, the hydrogen peroxide reacts with the surface carboxylic acid group, forming a peroxyacid structure (C(O)-O-OH), in the case of all three processes. In addition, molecular modeling for the processes with three different aromatic precursors was carried out. When combining these modeling results with the experimental research data, new interesting aspects of the film growth, reactions, and properties are exploited.

The ferroelectricity in fluorite oxides has gained increasing interest due to its promising properties for multiple applications in semiconductor as well as energy devices. The structural origin of the unexpected ferroelectricity is now believed to be the formation of a non-centrosymmetric orthorhombic phase with the space group of Pca2₁. However, the factors driving the formation of the ferroelectric phase are still under debate. In this study, to understand the effect of annealing temperature, the crystallization process of doped HfO₂ thin films is analyzed using in situ, high-temperature X-ray diffraction. The change in phase fractions in a multiphase system accompanied with the unit cell volume increase during annealing could be directly observed from X-ray diffraction analyses, and the observations give an information toward understanding the effect of annealing temperature on the structure and electrical properties. A strong coupling between the structure and the electrical properties is reconfirmed from this result.