The Arrival of the Digital Age in Glass Coating

H. Hagenström, T. Strietzel, A. Nilsson

Architectural glass coating is a mature technology with equipment and processes that show some, but no significant, differences between producing companies or equipment suppliers. Most players in the market apply a similar technology on similar equipment.

Therefore, mature markets lead to significant cost pressure which can best be dealt with if the productivity of a specific coating line is high and a good share of products with a high added value are produced. In other words, higher profits can be obtained if producers of coated glass are able to work at a minimum down-time and control complex layer stacks with a small team.

These requirements translate into the topic of this article: Improvement of process control and increase of productivity with advanced technology. We would like to show how data collection, data analysis and data processing can contribute to meeting the current market challenges. Our solutions are bundled under the name of VA INDIGO that has a scope from process support to digital services.

VON ARDENNE has established itself as a vital supplier for the vacuum coating industry for more than 40 years. The company offers a portfolio of solutions covering many applications, especially for flat substrates and large coating areas and is a leading provider, not only of equipment, but also of process technology.

In the 1990ies, VON ARDENNE was among the first to offer a plasma emission monitor that allows optical process control in an industrial environment. Many of the customers have initially applied the first-generation PEM05, then the VAprocos and now the VAprocos2 process control system to enable transition mode sputtering from planar and rotatable targets.

In the evolution of the hardware and software of this process control system, other sensors have been included such as lambda probes and voltage control devices. Therefore, the system supports the combined operation of these additional sensors.

Upon customer request, VON ARDENNE has established an alternative integrated solution for optical measurement: the ExSitu measuring system. Furthermore, VON ARDENNE has successfully launched their Online Trimming & Shimming Service.

It allows customers to adjust the coating uniformity of single magnetrons based on the ExSitu measurement data of single layers and predict the best gas trim and magnet bar shimming. This calculation saves a lot of time compared to the previous trial and error approach used for the optimization of magnetron uniformity.

GC330 Glass Coating System

GC330 Glass Coating System

Building on this experience and combining it with even more technical solutions provided by the market, we are now targeting a unified process control system that provides automated feedback control. Until now, only a part of the process has been stabilized (for instance with VAprocos). Or the systems are not used in automated feedback mode, for example the BREIN system of Wolfgang Theiss.

VON ARDENNE has launched a project to automate the coating process in two steps. The core of the system is a control algorithm, which uses optical information about the layer stack to determine if the layer thickness or layer thickness uniformity across the glass need to be adjusted to obtain the desired optical results. VA has successfully implemented this solution in 2020 and we are continuously improving the software and adding features to improve the usability and widening the scope of VA INDIGO portfolio.

In a second step, the performance will be enhanced by adding automatic recipe changes from one layer-stack product to another – or a process ramp-up after maintenance. Managing the production of complex layer stacks will be significantly simplified with the help of these process control features and will lead to a more stable production and increased uptime.

The above-mentioned solutions are tightly linked to the sputtering process. With regard to the final product quality control and the production costs, however, even more aspects of the system should be considered. For some years now, the term “Industrie 4.0” has been used to describe actions and tools that take advantage of the entire range of accessible data in a production system.

“We believe that three fundamental areas can be distinguished when referring to coating systems”, said Harald Hagenström, Vice President Glass at VON ARDENNE:

  • Process control as described above
  • Statistical analysis of any type of production data to enhance product quality and reduce cost (sometimes referred to as a “big data” approach)
  • Using system data to reduce maintenance cost and increasing the up-time of coating systems by means of predictive maintenance

VON ARDENNE has started to explore concepts and architectures that can serve as a basis for these solutions. High benefits may be gained if suppliers and users work closely together. We invite you to contact us for further information. As most exhibitions in 2020 have been cancelled, VON ARDENNE will participate digitally wherever we can.