ECE Spinout company NS Nanotech releases first solid-state semiconductor to produce human-safe disinfecting UV light

In the midst of the COVID-19 pandemic, many people became suddenly and acutely aware of airborne viral spread. In addition to COVID, the common cold, respiratory syncytial virus (RSV), measles, and the flu may all be passed between people through the air they breathe. NS Nanotech, a U-M Electrical and Computer Engineering spinout company co-founded by Prof. Zetian Mi in 2017 with the help of Innovation Partnerships, has designed a solution to mitigate this airborne infection.

Since the late 19th century, scientists have known that ultraviolet light has killed microorganisms, especially at the short UV-C wavelengths (180-280 nm). Traditionally, low-pressure mercury bulbs have been used to generate UV-C light around 254 nm, to disinfect air, water, and surfaces. However, this wavelength is dangerous to human skin and eyes, so it is restricted to settings and applications where humans are not immediately present. This leaves a gap in places where patients, healthcare workers, and the general public may be exposed to airborne infection, especially in small, enclosed spaces.

To fill this gap in protection, NS Nanotech developed a Far-UVC ShortWaveLight 215™ Emitter, which safely disinfects air and surfaces in spaces where people are working and going about their daily lives. This device, which is now available to manufacturing partners and application developers, is a nitride semiconductor cathodoluminescent lamp. It is much cheaper and easier to deploy than the krypton chloride excimer lamps (222 nm emitting) that are the current state-of-the-art devices on the market.

Mi’s research group has been a frontrunner in developing III-nitride materials and semiconductors, optoelectronic devices, light-emitting diodes, and UV photonics, for a range of research applications, including water and air purification and disinfection.

“We are excited by the enormous potential of this semiconductor-based technology. It offers an alternative path for air purification and disinfection, compared to conventional, inefficient, and bulky gas lamps,” said Mi. “Moreover, operating in the far UV-C spectrum, it is safer and more effective than traditional UV light.”

“To the best of our knowledge, this is the highest energy photon any semiconductor device has ever made, in any market, anywhere,” added Seth Coe-Sullivan, co-founder and CEO of NS Nanotech. “The light still does a great job of killing germs but it won’t penetrate our dead skin cells or the tear layer at the front of our eye. We think this product is really great for confined spaces, what we call ‘personal breathing zones.’”

The NS Nanotech team is starting with enclosed, high-value spaces for deployment of the lamps. Many of these applications are in the transportation industry, such as ambulances, school buses, and shuttles for senior citizens. Since the ShortWaveLight 215™ Emitter is the first of its kind in the world, NS Nanotech is helping its customers design the consumer products that will ultimately be deployed in these spaces.

“We’re really looking for what that killer app is going to be––we love hearing about new applications. By marketing business-to-business, we really want a broad set of customers to be able to try this out and deploy it,” Coe-Sullivan emphasized.

The devices are developed and assembled at NS Nanotech’s facility in Ann Arbor. Their team includes co-founder and ECE alum Rick Bolander (BSE MSE EE ‘83 ‘85), Mi research group alum David Laleyan (MS PhD ECE ‘19 ‘20), and Materials Science & Engineering alum Matt Stevenson. NS Nanotech hopes to continue this work by developing far-UVC LED lights for the same applications, a process that requires more complex technologies and a longer timeline.

Mi and the University of Michigan have a financial interest in NS Nanotech. The solid-state semiconductor product that NS Nanotech developed is based on intellectual property invented at the University of Michigan and licensed to NS Nanotech.