Inside one of Intel's 10 Technology Research labs in Hillsboro, Oregon, scientists are working to innovate new photoresist material designed to perform an extraordinarily precise job, and then completely disappear. Photoresists are not a permanent component of a computer chip, but continually evolving them is crucial to build the next generation of digital technology.
This delicate chemistry is at the heart of Intel’s semiconductor manufacturing photoresist science. It serves as a crucial foundation for Intel's ongoing EUV (extreme ultraviolet) lithography research, helping push the boundaries of what is physically possible in silicon manufacturing. By developing new chemical formulations, Intel is unlocking the full capabilities of High NA EUV (high numerical aperture extreme ultraviolet) lithography tools.
The Physics of High NA EUV and Transistor Scaling
As the global demand for computing power increases, the semiconductor industry is working to pack more transistors onto silicon wafers. Smaller, denser transistors take up less space, operate faster and consume less energy, directly translating to more powerful and efficient devices.
To print these microscopic switches, you need an advanced resolution printing capability. Standard EUV lithography uses a wavelength of light just 13.5 nanometers wide with an aperture of 0.33 to etch patterns onto wafers. High NA EUV takes this further, increasing the aperture to 0.55 and using curved internal mirrors to focus that light from a wider angle. This shrinks the maximum resolution these tools can achieve from 13 nanometers down to just 8 nanometers.
But printing at this resolution requires a matching evolution in chemistry. The photoresist material - acting as the "ink" for these massive machines - must become thinner to support finer lines, yet remain robust enough to withstand the subsequent etching phases. Once the pattern is successfully transferred, the photoresist is completely removed.
A New Frontier in Semiconductor Manufacturing Photoresist Science
To meet this challenge, Intel’s chemists and physicists collaborate with global suppliers and research universities. Together, they are experimenting with novel chemical elements to create more resilient materials.
"One of the new things we're looking at is metal oxide, so that's kind of new," Doczy says. "We're looking at metal oxide resist, and we think that that's going to be the new way for High NA EUV."
Within the Hillsboro R&D facility, which connects directly to a football-field-sized research fab, engineers test these experimental liquids. They dispense the resist onto silicon, spin it to create a perfectly uniform coating, and harden it in specialized ovens.
From there, the test silicon is placed in a small-scale EUV tool. Researchers monitor the chemical transformations in real-time to pinpoint exactly how photons interact with the resist. This rapid feedback loop allows the team to understand why a material succeeds or fails, accelerating the development cycle.
From Lab Breakthroughs to Mainstream Manufacturing
This relentless search for atomic-scale precision is the starting point for new innovations in Intel Foundry’s manufacturing nodes. It can take a decade of trial and error before a laboratory discovery is ready for high-volume manufacturing.
If a new photoresist formulation proves consistent and scalable, it graduates from the research lab to the adjacent research fab. Only after proving its reliability at scale does it transition into Intel’s high-volume commercial fabs.
This rigorous R&D pipeline is the same process that birthed Intel 18A innovations like RibbonFET and PowerVia. Both technologies required more than 10 years of persistent research before reaching maturity.
"It's really cool to see our stuff actually making it into product and knowing the years that went into it prior to that and where it was, and how risky it was," Doczy said.