To ensure the highest level of quality in photochemical etching (PCE), strict process controls must be implemented and every single process step must be carefully monitored and inspected. This includes controlling the temperature, concentration, and movement of the etching solution, the correct exposure and development of the photoresist mask, and verifying the accuracy of the etched structures using sophisticated measurement technology.
Quality aspects are of decisive importance in photochemical etching, as the precision of the process directly influences the accuracy and reliability of the end product. PCE is a subtractive manufacturing process in which material is removed from a metal sheet using a chemical solution and a photoresist mask. The process enables the production of complex shapes and patterns with high precision and is therefore widely used in industries such as aerospace, medical technology, and electronics. However, even minor deviations from the exact design specifications can lead to defective components that impair the functionality and safety of the end product.
To ensure the highest quality, strict process controls must be established, and every step in the process must be carefully monitored and inspected. This includes controlling the temperature, concentration, and movement of the etching solution, the correct exposure and development of the photoresist mask, and checking the dimensional accuracy of the etched structures using modern measurement technology. By adhering to tight tolerances and consistent quality standards, manufacturers can produce reliable, high-quality components that meet the demanding requirements of their customers.
In the following, Michael Kern, Head of Quality Management at the leading PCE innovator micrometal, explains the topic of quality and how the company meets the high requirements of its customers.
What does quality mean at micrometal?
Quality is at the heart of all activities at micrometal. We are a service provider for customers from a wide range of industries. Therefore, we must meet both the high requirements of globally active corporations and the needs of smaller companies. We are convinced that we can only fulfill our promise of being a reliable and long-term partner through the highest quality.
This also includes our contribution to our customers’ manufacturing processes, as our performance has a major influence on how efficiently their production lines operate without disruption over long periods. Another important aspect is the appearance of the products. We want our customers’ products to “look perfect.” This means that our quality standards ensure that the products are durable and trouble-free throughout their entire service life.
Furthermore, the products we manufacture are far from ordinary metal parts. They are often geometrically complex and require maximum repeatability—something that can only be achieved efficiently with PCE.
Since micrometal focuses on high-volume applications—what requirements does this place on your quality management?
Imagine a single defective part is on a reel with a length of one kilometer—the production of which takes hours—and the entire reel has to be discarded. In addition, we usually do not just produce one reel at a time, but several in parallel in a continuous process. This means we cannot simply stop production, remove the defect, and continue.
To ensure efficient production, we therefore require effective control measures in all areas. We have built up an extremely reliable supplier base whose partners deliver high-precision, high-quality raw materials that are optimally suited for our process.
Our self-developed and manufactured tools are based on decades of experience and can be cost-effectively optimized to achieve the highest repeatability and optimal etching conditions.
Our process is monitored continuously and in real time to avoid errors and to keep the multitude of process parameters within the narrow tolerance windows required for our next-generation PCE process.
However, since errors cannot be completely avoided in PCE, we have technologies for error detection during production as well as countermeasures to keep the yield high.
As our market-leading PCE process pushes the boundaries of what is technically feasible, the quality assurance systems in the production environment are also working at their performance limits. For this reason, we carry out a 100% inspection of our products in the downstream process to ensure that we actually achieve the promised quality.
How is quality assurance divided between production and the laboratory?
Roughly speaking, about 50:50. As already mentioned, we carry out many measurements during tool manufacture and production to control the process. However, it is not possible to fully monitor all features and dimensions directly in production during a continuous, dynamic PCE process.
In the downstream 100% inspection, we then have the time and the technical capabilities to comprehensively check all relevant parameters.
Conversely, the production team benefits from the findings and data of these inspections in subsequent production runs.
What do you mean by a 100% inspection?
For us, 100% inspection is a downstream quality process in which every single manufactured part is fully checked using state-of-the-art technological means. The goal is to detect even the smallest deviations from the target state and treat them accordingly. In this way, we achieve maximum repeatability, reproducibility, and reliability for our products.
Can you guarantee your customers a zero-defect rate? If so, how?
First of all, as with any manufacturing process, deviations can also occur during etching. However, through our comprehensive control methods, we minimize errors to the technical minimum.
Already in the design and sampling phase, we work with our customers to develop a fail-safe strategy to either remove defective parts from the delivered batches or mark them accordingly. This allows our customers’ highly automated production lines to reliably detect defective parts and handle them accordingly. That is a true zero-defect strategy.
How does micrometal’s perception of quality differ from other PCE providers?
I don’t think there are “standardized” PCE providers—every provider has its own special characteristics.
What sets us apart, however, is the exceptional quality of our etched components. We have compared numerous competitor products, and no one achieves such smooth structures, such tight tolerances, and thus such high precision as we do.
PCE remains a chemical process in which many variables can influence the result. While other providers accept certain deviations, we adjust our tools, process parameters, and control mechanisms until the desired result is achieved.
Is the development in quality management moving towards full automation?
micrometal monitors technological developments very closely and certainly sees potential for full automation in the future. However, as our next-generation PCE process is already working at the limit of what is technically feasible, full automation is not yet possible at this time.
Naturally, we reduce the influence of human factors as much as possible in every process step. In addition, we rely on risk analyses and optimization methods based on extensive data and experience to identify potential errors at an early stage and avoid them through appropriate measures.
What three things should potential customers know about your quality philosophy?
First: You will not find better quality in the field of etching.
Second: Quality always pays off in the long run—micrometal wins every ultra-marathon.
Third: Quality does not just consist of key figures. It opens up the possibility of thinking beyond what is currently feasible and realizing things that were previously considered impossible.
