Enabling the future of chipmaking

“If you are using the latest iPhones or the latest graphics processing units (GPUs) from multinational companies like NVIDIA, chances are they were manufactured using EUV technology,” says Dinesh Bettadapur, CEO of Birmingham-founded Irresistible Materials.

This technology can print chip features at a scale measured in atoms, but only if the material coating the chip’s silicon surface – a material known as “photoresist” – can hold that precision without blurring it. “In the future, if the photoresist happens to be ours,” continues Bettadapur, “then our material would have essentially enabled the most advanced chips powering the most advanced devices."

Since spinning out of the University of Birmingham in 2010, Irresistible Materials initially built its business around a family of chemical compounds called Fullerenes based on the research done at the University, developing them for various manufacturing applications. As EUV emerged in industry, Bettadapur recalls, “we felt that it could represent a very significant market opportunity, and so we wondered: what if we developed a photoresist material for EUV specifically?"

But developing a material for EUV meant finding a new balance between performance, practicality and the demands of chip manufacturers. It also required inventing a new material not based on Fullerenes to be able to meet the industry needs. “The requirements for EUV manufacturing are extremely challenging, it is the most advanced technology out there," highlights Bettadapur. Building on top of the two material platforms prevalent in the photoresist market – chemically amplified resists (CAR) and metal oxide resists (MOR) – Irresistible Materials introduced its Multi-Trigger Resist, or MTR™. “We had to come up with something new and different,” Bettadapur explains, “but we didn't want it to be so different that would make it harder to adopt, so we took the best of both worlds and combined them."

The result is a resist designed to make EUV patterns sharper, using a chemical reaction that switches on where the light hits and suppresses unwanted reactions elsewhere. Its unusually small organic molecules offer finer control at the nanoscale, while also being free of both damaging forever chemicals (“PFAS”) – which is “highly desirable from an environmental perspective”, and metal, which avoids contamination issues in wafer fabrication that are costly and time-consuming to fix afterwards.

The company is continuing to make rapid progress towards getting its material ready for commercialisation. It has secured a major round of financing and is actively collaborating with a major manufacturing supplier. “We are now on a firm footing and well positioned for market success, and ultimately, customer adoption,” Bettadapur says.

While the company operates in a global industry, the science stays close to home. Irresistible Materials' chemistry lab sits at Wolverhampton Science Park, and it draws on testing and characterisation support from universities across the Midlands, including Birmingham, Wolverhampton, Nottingham and Warwick. There is a planned move into a new integrated site in Kings Norton, Birmingham, bringing its team, cleanroom, chemistry lab and testing facility under one roof. "We are very fortunate to be in the Midlands area," Bettadapur notes, highlighting how “we believe the Midlands area provides the right environment to continue to hire, expand, and grow our team."

Birmingham holds equity from the original spin-out, and David Coleman, CEO of University of Birmingham Enterprise, sat on the Irresistible Materials board for several years before stepping down last year. "Being a spin-out, we got the know-how and the IP," Bettadapur observes. "Along the way, Enterprise has really invested in our success, making a series of investments at critical times in our journey. We have been fortunate to use some of their facilities for material development, and specialised services they offer for material testing and characterisation." Over time, the company has hired a number of lithographers and chemists straight out of Birmingham's chemistry and physics departments too.

When Bettadapur joined the company from Silicon Valley, he found a veteran team: "Even though the company had been through many ups and downs, as any small company does, they all stuck to the task at hand and were committed to the company. That was good to see." And Bettadapur found himself equally attracted to the company’s mission: "this is an entrepreneurial company essentially trying to change the world," he says. "That's a huge challenge, of course, but if you're able to embrace that risk and help the company cross the technology chasm, it can be a huge accomplishment."