Four million people per year acquire health associated infections (HAIs) in Europe [1]. To reduce spreading of pathogens, a photocatalytic coating with superacid surface properties has been developed that offer dual action by means of surface generated protons and radical oxygen species. This antipathogenic coating contains only benign materials and does not involve compounds that could induce antibiotic resistance.
The antipathogenic action of the films is realized by acidifying the surface of crystalline TiO2 thin films using a reactive gas-phase photo-fixation process yielding strongly surface-bonded SO4 groups, while maintaining the photocatalytic properties of the film [2,3].
The TiO2-films are deposited using a rotatable dual magnetron system with ceramic titania targets in bipolar pulsed mode, followed by the crystallization by inline flash lamp annealing (FLA). Furnace annealing of the films was used for reference purposes. The TiO2-film crystallization process has been studied as a function of deposition parameters, including plasma pulse parameters and oxygen flow.
X-ray diffraction demonstrated that by adjusting the PVD process the crystalline state after the annealing process, whether by furnace annealing or inline FLA, can be controlled to adjust the TiO2 crystallization enabling photo-fixation of SO4, as verified by X-ray photoelectron spectroscopy. The temperature for the formation of crystalline TiO2 thin films has been studied, giving a lowest value for anatase crystallization to 225°C, which makes the process compatible with temperature resistive polymer substrates.
To understand the crystallization process of the inline FLA, simulations of the temperature profile were done and correlated with the furnace annealing process. This indicates the potential of linking the PVD process and the FLA process, which offers future possibilities to transfer the process to polymer substrates.
In conclusion, we have demonstrated that crystalline TiO2 coating can be applied on large substrate areas at moderate substrate temperature giving the opportunity to photo-adsorb sulfate groups on high-temperature resistant polymer substrates, thus suggesting a pathway for synthesis of antipathogenic foils by roll-to-roll processes. This study is a part of the funded project SANFLEX (m ERANET, grant no 685451).
References:[1] C. Suetens et al., “Prevalence of healthcare-associated infections, estimated incidence and composite antimicrobial resistance index in acute care hospitals and long-term care facilities: results from two European point prevalence surveys, 2016 to 2017”, Eurosurveillance, 2018, vol. 23/46.[2] D. Langhammer, J. Kullgren and L. Österlund: “Photoinduced Adsorption and Oxidation of SO2 on Anatase TiO2(101)”, J. Am. Chem. Soc. 2020, 142(52), 21767–21774.[3] Z. Topalian, et al., Adsorption and photo-oxidation of acetaldehyde on TiO2 and sulphate modified TiO2: Studies by in situ FTIR spectroscopy and micro-kinetic modelling, J. Catal. 2013, 307, 265-274.

A wide range of glass is coated and processed in a vacuum environment. The nature of a vacuum is inherently problematic especially when enacted on a very large scale and in high productivity environments. There is no such thing as a ‘leak’ free vacuum chamber, just the level of the leak, and also whether the nature of the leak will have an adverse effect on production quality and speed. The standard approach to assessing the vacuum quality is the pressure reading and helium leak checking. To a lesser extent, analysis of the trace gases via a quadrupole mass spectrometer (QMS) located in the vacuum is used to provide more definitive analysis. Gas analysis is a powerful tool as it provides a total picture of species present, and this can be used to track production quality and the effect any unexpected or unwanted variations. It can provide on-line chamber atmospheric leak rates, leak rates of chamber components, substrate and chamber moisture outgassing rates, as well as the quality and ratio of process gases. All this information can be used to good effect to improve product quality and productivity.
Whilst the method of quadrupole mass spectrometry (QMS) is long established, it has not been widely taken advantage of in large area glass coating. The reason lies in a lack of industrial robustness and the difficulty in maintaining the operation of the QMS method on large systems and with skill sets of typical operators running the plants.
More recently, the method of remote plasma optical emission spectroscopy (RPOES) has been shown as a very important tool to track gas species in an industrial vacuum environment. The popularity of RPOES lies solely with its inherent industrially robustness compared to quadrupole mass spectrometry (QMS) methods, operators cannot break it! When relying on gas analysis to provide information key to maintaining a production process, it is critical that the method is always providing information, i.e. no down-time. The reliable data provided by RPOES can be used to establish closed loop control of many machine functions as well as a foundation for artificial intelligence-based decision making. A well-established application is the monitoring and high-speed control of reactive sputtering processes where the RPOES provides the ‘sensing’ of the gaseous conditions of the process, which is then input to a closed loop controller to maintain the process conditions for stable, high-rate thin film production.
The talk will give a detailed assessment of the method and the different uses within large area coating. The scientific merit of the method is to some degree still an ‘open box’ due to its unique characteristics. For example, it will also be shown how RPOES can monitor D, T, 4He, 3He and neon gas in ‘Fusion’ reactor exhausts with such speed and accuracy, that one of the key challenges to commercial viability of Fusion Energy can now be overcome.

The presentation at the International Conference on Coatings on Glass and Plastics (ICCG) will focus on the machinery development for industrial manufacturing of innovative switchable electrochromic (EC) films as a cost-effective retrofit solution for windows and glass facades. The FLEX-G 4.0 (BMWi funded) project aims to develop the pilot production process and demonstration of switchable electrochromic films. The upscaling of the small-scale (EC) films production process to a continuous roll-to-roll concept is essential for achieving higher production rates. This approach provides high speed, high efficiency, and minimal cycle time of continuous flow manufacturing, ultimately contributing to increased output and reduced costs per unit. Additionally, roll-to-roll manufacturing enables real-time monitoring of parameters such as thickness, temperature, and coating uniformity, allowing for rapid detection of deviations from desired specifications. This approach also minimizes material waste compared to batch processing, with less setup waste between batches, leading to more efficient material utilization. The development of system designs and manufacturing technologies will be discussed, as well as the production process requirements of large-area EC films. The presentation will shed light on the transition from small-scale production to continuous roll-to-roll manufacturing, emphasizing the benefits of this approach in terms of increased production rates and cost-effectiveness. The insights shared aim to contribute to the advancement of industrial manufacturing processes for innovative EC films and their applications in energy-efficient windows.

Anti-reflection (AR) coatings play a pivotal role in enhancing the power output of solar modules by eliminating reflection losses at the air-cover glass interface [1]. Due to enhanced solar transmission AR coated front cover glass solutions dominate the PV market [2]. Single-layer Sol-Gel based coatings are compelling due to their streamlined application, scalability, cost-effectiveness, durability and broad-spectrum AR properties [1, 3]. In this investigation, we explore the viability of employing a Tetraethyl orthosilicate (TEOS) based spraying solution, which can be directly administered onto flat glass surfaces with air atomizing nozzles at substrate temperatures exceeding 500°C. The compatibility of spray process with hot glass deposition is appealing because it opens the possibility of cost-effective online production with continuous glass ribbon substrates. Our findings demonstrate that the coatings produced through this method exhibit thickness uniformity, conformally coat patterned glasses, and withstand a subsequent industrial tempering process without compromising their anti-reflection properties. Finally, we investigate the potential of employing a secondary spray application with organically modified silica precursors for improved weathering durability.

References

[1] D. Chen, „Anti-reflection (AR) coatings made by sol–gel processes: A review,“ Solar Energy Materials and Solar Cells, vol. 68, no. 3-4, pp. 313-336, 2001.[2] „International Technology Roadmap for Photovoltaic (ITRPV). 14th ed.,“ VDMA, Frankfurt, 2023.[3] Y. Zeng, N. Song, S. Lim, M. Keevers, Y. Wu, Z. Yang, S. Pillai, J. Y. Jiang and M. Green, „Comparative durability study of commercial inner-pore antireflection coatings and alternative dense coatings,“ Solar Energy Materials and Solar Cells, vol. 251, p. 112122, 2023.

Plasma-driven coating processes like PECVD and magnetron sputtering play a crucial role in various aspects of the thin film deposition industry, particularly in precision manufacturing processes such as optical coatings. The properties of deposited films depend on the choice of precursor gases (organic, inorganic) and on plasma-surface interactions. The precursor chemistry is driven by the plasma density and electron temperature, while the plasma-surface interactions are driven by the plasma potential and surface biases, and substrate temperature. These fundamental process drivers are all challenging to directly measure, especially in an industrial chamber. Reactive plasma sputtering processes additionally exhibit a hysteresis effect, further complicating the understanding of tool conditions for process development and control.
To meet the challenges of tighter process windows, and of process transfer from research labs to industry, measurements of the fundamental process drivers are required. Impedans Ltd offers a comprehensive suite of plasma diagnostic tools [1]. The RF-compensated, self-cleaning Langmuir probes by Impedans give precise measurements of electron density, temperature, and plasma potentials, enabling the generation of spatial and temporal profiles within the plasma to ensure uniformity across large surface areas. Additionally, Impedans provides the novel Plato Langmuir probe tailored for high deposition rate coating tools, providing insight into their plasma parameters for the first time [2]. The Quantum ion energy analyzer directly measures the ion energy and flux impacting the substrate, enabling exact control over the structural attributes of deposited thin films and facilitating process transfer by aligning ion/neutral ratios from tool to tool. Lastly, the Octiv VI probes monitor plasma current, voltage, and impedance for RF and Pulsed DC sources, ensuring process repeatability [3]. This talk will present the applications of these sensors across diverse thin film deposition systems for process development and improvement.
References[1] Impedans Ltd, Dublin, Ireland [www.impedans.com] [2] Artem Shelemin et al, J. Vac. Sci. Technol. A 39, 063003 (2021)[3] J Roggendorf et al Plasma Sources Sci. Technol. 31 065007 (2022)

The need for reliable measurement techniques for optical characterization of thin films is growing. In the past, we have developed tools for measuring directional optical properties in the solar range which have proven to be a valuable instrument evaluating thin film properties by variable angle spectroscopy.
We recently have extended this measurement capability by developing a similar goniometer-based system for the infrared, allowing to measure transmittance and reflectance for angles of incidence ranging from (near-)normal incidence to values as high as 85 degrees depending on the sample size. The wavelength range of this tool is between 1.5 and 25 microns, mostly depending on the detector that is installed. Measurements can be performed at P and S polarization separately and are completely automated. We also developed an autosampler for the same system, that allows automated measurements on multiple samples, such as a reference standard, in one measurement series.
Examples of experimental results are given to demonstrate the value of this technique for various coating applications

This presentation delves into the crucial role of In-Line Color Control in glass production, emphasizing its significance in maintaining color stability and addressing the functional aspects of glass beyond aesthetics. Applications include Low-E Glass for energy efficiency in different climates, Sun Protection Glass for temperature regulation, and Colored Glass for aesthetic appeal. An inline spectrophotometer is highlighted for its In-Line spectral color measurement capabilities, ensuring accuracy and real-time quality control. The instrument’s ability to measure reflectance at various angles contributes to consistent results, aligning with human visual perception. Other instruments offer specialized measurements for different glass properties. Overall, the integration of advanced spectrophotometry technology enhances energy-efficient architecture, meeting the demands of architects, energy regulations, and quality standards.

Applications:
1. Low-E Glass: In colder regions, the coating on glass allows near-infrared energy from the sun to pass through, warming up the room. However, once heated, the coating reflects long infrared wavelengths, preventing heat loss and contributing to energy conservation.
2. Sun Protection Glass: In sunnier climates, glass coatings are designed to reflect infrared energy, keeping buildings cooler. The thickness and composition of these layers impact the color of the glass. In-Line Color Control ensures the accuracy of each layer’s spectral properties, maintaining consistent quality.
3. Colored Glass: Architects often desire specific colors on glass for aesthetic reasons. When combined with solar control coatings, the color may vary based on the viewing angle and illumination conditions. Modern spectrophotometers address this challenge by measuring spectral curves under different angles and illuminations, ensuring color consistency.

ROI:
An inline coil coating color control system offers fast ROI, usually within 6 months.
• Reduces primer and powder coating costs, waste, and rework
• Catches color issues early, saving a modern coating line ≈$50,000/month
• Offers visibility to all stakeholders and tracks results for a revenue increase of ≈5%

Conclusion: In the pursuit of energy-efficient architecture, the role of glass extends beyond aesthetics to functionality. In-Line Color Control, facilitated by advanced spectrophotometers, ensures the stability of the glass coating process, meeting the demands of architects, energy efficiency regulations, and quality standards. The integration of such technology contributes to sustainable building practices and enhances the overall performance of coated glass in diverse environmental conditions.

Global strategies have been developed to reach net-zero-emissions in the next decades. Different regions of the world have committed to different timelines. But they all push carbon producers to develop strategies to reduce their carbon footprint. Manufacturing companies have a large share on those regional footprints, leading to an increased pressure in the future to reduce CO2 or to compensate it. On the other hand, manufacturers are also economically oriented companies that pursue goals such as sales growth and cost reduction in order to enable overall profit growth.

In order to achieve both – greater sustainability by reducing the carbon footprint and higher profits – various approaches are possible. In this session we will show how digitalization can support both goals. The basic production technology for energy-efficient glass and plastic coatings was established about decades ago. Now, new digital solutions are raising resource efficiency in production to a significantly higher level. We show by specific examples (VA PROCESSMASTER, VA RECIPEMASTER, VA TIPCOS) how software-based automation increases productivity based on time savings while at the same time reducing resource losses e.g. material or energy. Out-of-specification losses due to process drift are avoided, the energy efficiency of process working points is optimized, and complex changes of production tool states can be automated and thus optimized accordingly to reduce resource losses caused by human error. In summary, modern software solutions help minimizing the carbon footprint of coating products while at the same time enabling the increase of yield and profit.

Ultra-thin glass is an attractive flexible substrate for coating applications, e.g. foldable displays, wearables etc. Beside these main applications, the conscious use of resources is another top issue of our time. Thus, many new ideas are developed with respect to weight reduction of components or upgrade solutions using light-weight flexible substrates retrofitted to existing products. Ultra-thin glass is readily considered for such approaches and often tested at laboratory scale. However, the brittleness of glass is still a challenge in industrial processes. Glass fracture typically happens randomly and suddenly. Thus, the mechanical stability of the ultra-thin glass is essential during handling, functionalization and within the device. To maintain the stability of the glass, crucial parameters like mechanical thin film stress and the substrate strength must be under tighter control than for conventional materials. Therefore, the influence of each processing step on the strength of the ultra-thin glass must be known. Random sampling as well as structured investigations are useful for this purpose. However, many conventional strength testing methods are not suited for the characterization of ultra-thin glass due to its thickness of only 100 µm or less. This presentation will provide an overview of suitable test methods to characterize the mechanical behavior of ultra-thin glass. Moreover, the influence of magnetron sputtered thin films on the substrate strength will be discussed. The focus of the presented results will be on industrially relevant use cases like transparent conductive oxides and antireflective coating systems.

Glass can be found in many areas of everyday life, from life science, food, packaging, solar thermal energy, building technology, motor vehicles, electronics and so on. The reasons for these diverse areas of application are due to the properties of glass, first and foremost its good transparency. However, its good chemical resistance, thermal resistance and good electrical and thermal insulation properties also predestine this material for these applications. But hardly anyone is aware that not all glass is the same and how glass becomes what we use almost every day.
An important aspect of glass processing is surface finish. As it is a transparent material, numerous efforts are made to improve this transparency through coatings, to functionalize surfaces and to enhance the stability of the entire glass. However, the brittle-hard material also has certain limits in terms of machinability. For example, glass lacks plastic deformability, so that even the smallest damage to the glass surface significantly reduces the load-bearing capacity of a component.
The most stable of all glass surfaces is the fire-polished surface. Fire polishing melts all surface defects away and smoothes rough surfaces. Fire polishing is usually carried out manually with a gas burner or, in some cases, semi-automatically. Plasma processes are also used. The disadvantage of both processes is the flame/plasma pressure, which has a negative effect on the molten surface. This is why laser polishing is becoming increasingly popular for more and more applications, as it is a forceless process that can be automated and controlled very easily. The surface is smoothed solely by the surface tension of the molten glass. Due to this effect, this process is also very suitable for rounding glass edges, which increases the stability of the glass enormously. CO2 lasers are used almost exclusively for glass, as the laser beam is almost 100% absorbed.
This article presents the laser polishing of glass. First, the equipment and system technology required for polishing glass in various dimensions and geometries is introduced. In the next step, the special features of the different types of glass are discussed. Not all glass is the same, as there are considerable differences in the processing temperature and the coefficient of expansion depending on the chemical composition. The laser and process parameters must therefore be set separately for each type of glass. The polishing process is also described, in particular the laser beam shaping and beam movement as well as the necessary temperature management during process control and glass handling. The adjustment of the corresponding laser and process parameters depending on the initial geometry and roughness is also discussed. A series of application examples and potential uses for the targeted influencing of glass surfaces with laser beam technology round off the presentation.

Vanadium dioxide-based coatings offer great potential for thermochromic switchable smart windows as they exhibit a significant change in optical transparency and reflectivity in the infrared spectrum. Here W doping of VO2 is used for the adjustment of the switching temperature. Additional Sr doping has been introduced by the Justus Liebig University Giessen to overcome the drawback of yellow-brownish color impression of the ternary VWO2.

In the course of the project »IntelVanaGlas«, the coating technology for VWSrO2 will be extended from laboratory scale to large-scale coating. We report on the project progress including the transition from laboratory scale rf-sputter deposition to large scale applicable DC sputter deposition, optical emission spectroscopy for process control and seed layer incorporation to promote proper Vanadium dioxide growth at lowered substrate temperature. Furthermore, the integration of additional dielectric layers for optimized optical properties will be discussed.

With constantly progressing climate change and global warming, we face the challenge to reduce our energy consumption and CO2 emission. In Europe, more than 1/3 of our total energy consumption results from buildings, where more than 30% of energy loss is due to dated inefficient windows. Here we present our development of the SunSmart thermochromic smart window for optimized solar heat management in buildings in continental and oceanic climates. Our proprietary smart window combines high visible transmission of up to 75% with high solar modulation of up to 23%. The material autonomously changes its solar heat transmission at a temperature around 21°C and transitions from an infrared transparent to blocking state, whilst staying fully transparent in the visible. In an optimized IGU this leads to a change in G value of up to 13% between the cold and the hot state. The use of the newly developed smart window can lead to annual energy and cost savings of approximately 1000 kWh and 20 €/m2 glass (500 € per year) for an average household in the Netherlands. The thermochromic technology is complementary to current low-e coatings and can be implemented in regular windows and frames without additional requirements for special installations like wiring. In addition to optical performance and impact on energy, cost and CO2 emission savings, we present the first 1 x 1 m2 demonstrator installed in a test building with monitoring of the thermochromic performance in real environment. Furthermore, we present the scale up of the thermochromic coating to 1 m2 glass plates within our newly established pilot line for liquid coating deposition using an industrial washing machine, an industrial roller coater and a specially designed furnace. Lastly, we give an outlook on application via a 2.5 m width roller coater and next steps towards commercialization of the new smart window.

With an increasing degree of automation in mobility, the demands on the sensors and the number of sensors in the vehicle are steadily increasing. For sensor integration and combination an efficiently manufacturable compound system including LiDAR, radar and lighting system has been designed. The challenge of the system development was to balance functional aspects and external design requirements for the integration into the headlight.
In the pilot project “Smart Headlight” of the PREAPRE program of the Fraunhofer Society the Fraunhofer institutes FEP, IOF, ILT, IMS and FHR will prove the integration of such a sensor-lighting combination into automotive headlights under shared coaxial decoupling in driving direction.
The optical system consists of two combiner components. Their four surfaces are coated to control the requirements of the sensor and lighting systems regarding their needed transmittance and reflectance covering a wavelength range between the nanometer scale [visible (VIS), infrared (IR)] and millimeter scale [radar wavelengths] under a broad range of angles of incidence. Multilayer optical interference coatings for this specific functionality are designed and manufactured at FEP Dresden.
The development of the thin film designs must consider for example the balance between a high reflecting band for coupling the LiDAR and an antireflective function for the transmittance of the lighting system in the VIS – both in directly neighbored wavelength ranges. A second combiner component must couple the radar signals and simultaneously provide low-loss transmission of lighting and LiDAR spectral range. The beam-shaping functionality for the radar system is realized by laser structuring of the radar-facing multilayer reflector.
A similar principle of structuring conductive coating materials in optical multilayer systems can also be interesting for the optimization of architectural windows regarding mobile radio waves.
Practical aspects of these design developments and the manufacturing process of the sputtered coatings will be presented.