NSS Water: cleaning up semiconductor manufacturing at the molecular level
Semiconductor manufacturing is one of the most water-intensive industrial processes, but NSS Water is on a mission to change this. The company is developing water purification technology that is designed to meet the stringent requirements of advanced chip fabrication head-on, while also reducing overall water and chemical consumption.
Founded by Björn Holmström, Founder and CEO, NSS Water focuses on producing water that is as close to pure H₂O as possible. This is currently used in semiconductor manufacturing, research, and laboratory environments. The company’s technology is based on membrane distillation, extracting individual water molecules from a given feed source.
What began as a measurement challenge has now evolved into a much larger solution that helps to improve yield, process control, and sustainability in chip production.
THE JOURNEY
Holmström’s route into ultra-pure water was unconventional.
His early career included working as a lock keeper, followed by roles in electronics manufacturing at Ericsson in Stockholm, where he gained experience in circuit board production and radio-frequency components. He later studied Process Engineering and completed an internship at Rejlers, before working there for several years in process engineering and product management roles.
While working as a process engineer, Holmström began developing what would become NSS Water. However, at the time it was only a side project … until it gradually grew into a full-time venture.
A SIDE PROJECT THAT BECAME A COMPANY
NSS Water was born from a space-related research project where Holmström was tasked with producing reference materials for measuring nanoparticles in water under zero-gravity conditions.
However, the challenge lay in the fact that the project required water of a purity level that was not commercially available. “For doing this ‘recipe’, we needed pure water, and no water that we found was pure enough. So we started looking into different technologies for producing water.”
That search led to membrane distillation and the realisation that, with adaptation, it could deliver far higher purity than what had previously been attainable with conventional systems.
WHY WATER PURITY MATTERS IN CHIPMAKING
Water is used continuously throughout the semiconductor manufacturing process, particularly for cleaning silicon wafers before, during, and after processing. Even minute contamination can compromise yield.
Holmström noted that metal ions, salts, and other contaminants can damage wafers or interfere with manufacturing steps, especially as feature sizes continue to shrink. A standard silicon wafer measures 300mm in diameter, yet particles measuring only five to 20 nanometres can cause defects.
By improving water purity, manufacturers can reduce contamination risk and increase yield. Holmström explained that if a production run of 100 chips achieves a 50% yield, half of those devices are lost. By improving the quality of the water, it directly supports higher usable output.
NSS Water’s system is designed to remove particles down to the five to 10 nanometre range. Holmström believes smaller sizes may be achievable in theory, but in reality, being able to measure anything smaller would be problematic.
MEASURING SOMETHING THAT DOES NOT WANT TO STAY PURE
Accurately measuring water purity remains one of the biggest challenges today.
Pure water, Holmström explained, is “aggressive”. It readily absorbs contaminants from anything it touches, including containers used for sampling. Sending samples to external laboratories can therefore undermine accuracy, as contamination can be introduced during transport and storage.
This makes fast, accurate, onsite measurement vital. NSS Water’s technology takes reliance off laboratory testing and supports tighter process control at the point of use.
THE ROAD TO ADOPTION
While the technology addresses a clear technical problem, commercialising it is much more complex. Despite semiconductors being the foundational components of many, if not all, devices today, the semiconductor industry is a conservative one, and it is a barrier when it comes to securing industry validation and funding. “We have industry players saying that the way we are approaching the challenge is correct, but it requires a lot of funding and a lot of time.”
However, Europe’s semiconductor manufacturing base is currently more focused on mature automotive processes, where the requirement for water purity is less demanding. As a result, validation opportunities are to be found in regions such as South Korea, Taiwan, and the US, where Holmström has spent significant time building relationships and understanding local startup ecosystems.
PARTNERSHIPS AS A ROUTE TO CREDIBILITY
Industry collaborators act as sounding boards, helping to validate the company’s roadmap and refine its technical direction, which is central to the company’s progress.
By engaging directly with potential customers and partners, NSS Water has been able to adapt its development priorities while building the credibility needed to move towards commercial deployment.
SUSTAINABILITY AS AN OUTCOME
Sustainability is another benefit of the technology. Early tests revealed that ultra-pure water could drastically reduce the volume needed to clean wafers, as well as the consumption of chemicals in the process. This not only lowers costs but also lessens environmental impact, which, given that the semiconductor industry is one of the most environmentally negative industries, is a key consideration as the tech industry faces increasing pressure to enhance resource efficiency and reduce waste.
LOOKING AHEAD
The next five years are expected to be intensive, with a focus on product development, validation, and early commercialisation.
Holmström ultimately sees multiple possible outcomes, from scaling NSS Water as an independent supplier to integration within a larger industrial player.
For now, the company’s direction is captured in its own description of what it does: “Reinventing semiconductors one drop of water at a time.”
This article originally appeared in the January/February 2026 issue of Startups Magazine. Click here to subscribe
