Over the past years, cosine has significantly expanded its cleanroom capabilities to strengthen contamination control in support of both its High-Energy Optics (HEO) and Remote Sensing activities for safety and resilience. These efforts play a key role in major projects, from the production of ESA’s NewAthena Silicon Pore Optics (SPO) to the sensors of the Dutch Ministry of Defence’s PAMI programme, Valk and TSCOUT HP.
At the heart of this work lies a critical challenge: ensuring optical systems perform flawlessly by keeping out even the tiniest particles that could compromise performance. Whether it’s bonding 150,000 silicon mirrors for an X-ray telescope or guaranteeing reliability for Earth observation instruments, cleanliness is non-negotiable. To meet this challenge, cosine has built strong expertise in contamination control and developed its own metrology, combining semiconductor-industry techniques with space-grade requirements.
“The scale of NewAthena makes the challenge quite unique. We are compactifying approximately 300 m² of mirror surface area into one 2.6 m optic. This is more than ten times the surface of the JWST’s polished mirror area. Any particle stuck in the process could have a negative effect on performance,” explains Luc Voruz, Senior Scientist at cosine. “Once the telescope is in space, there is no chance to repair or clean it, so prevention is paramount.” On the Remote Sensing side of the company, “we design and manufacture large open-aperture reflective telescopes for Earth Observation and beyond, where particle contamination on the mirrors could directly contribute to straylight, so maintaining a pristine workspace is critical,” says Dr Nathan Vercruyssen, Senior Scientist at cosine.
Cleaning and keeping clean
cosine’s approach follows two principles: remove and prevent. Cleaning is achieved through a well-established industrial process from the semiconductor industry, using automated wet benches, which are used to clean millions of wafers worldwide every day. Prevention is then ensured through various efforts.
More generally at cosine, “we increased our cleanroom capacity to over 1,000 m2 to host cutting-edge equipment and to give our staff more workspace in a clean environment with constantly monitored air quality. We also designed and built a fully automated particle detection system for quality assurance and to assist process development. On top of that, we strengthened our metrology by adding new tools such as particle counters, fallout scanners and witness samples to monitor particulate and molecular contamination inside the cleanrooms”, explains Voruz.
Partnerships also play a role. “We actively collaborate with ESA/ESTEC on contamination control techniques, organised a dedicated workshop together, and joined the Dutch network of companies involved in contamination control (VCCN). We also conduct regular inspections and retrain our staff. It is not only about cleaning, but about staying clean.”
By strengthening its capabilities in contamination control, cosine enables ambitious space missions such as NewAthena while ensuring resilience and reliability in Earth observation solutions. This cross-sector expertise bridges semiconductor precision with the demands of some of the most ambitious space and defence missions, positioning cosine at the forefront of innovative space companies.
Read more information about ESA’s NewAthena mission.
About cosine
cosine is a leading worldwide company in the development of space instrumentation, such as Silicon Pore Optics for astronomy and remote sensing solutions with onboard analytics for Earth Observation and planetary science. cosine combines physics and technology to bring out-of-the-box solutions to its clients. cosine has been developing and delivering innovative measurement systems for space and industrial applications since 1998. The company operates more than 1,000 m2 of cleanrooms and high-tech assembly facilities to build and test the systems we produce for customers at our headquarters in Sassenheim, The Netherlands and at subsidiaries in Berlin, Germany and Benevento, Italy.
