Researchers develop holes 60,000 times smaller than human hair
New process offers extreme precision that could revolutionize medical diagnostics and beyond.
KTH PhD student Fabio De Ferrari and colleagues have discovered a cost-effective way to create ultra-small pores in silicon - smaller than 5 nanometers in diameter.
Using gold nanoparticles and a method called metal-assisted chemical etching, the researchers also discovered a self-limiting effect—like a drill that stops automatically at just the right depth—making the technique highly precise and scalable.
Applications beyond medicine
The breakthrough, published in ACS Applied Materials & Interfaces , offers a scalable alternative to the highly specialized and expensive equipment typically required for fabricating such tiny pores," explains De Ferrari, who is lead author of the new study.
"While traditional methods often rely on elaborate serial techniques, our approach enables batch processing using an efficient chemical reaction."
Because the method works with existing semiconductor production processes, its applications extend beyond medicine to include disease detection, water contamination monitoring, and protein analysis.
“These nanopores are 60,000 times smaller than the diameter of a human hair,” he explains.
“The most surprising part was that gold nanoparticles of different sizes, from 10 to 40 nanometers, all resulted in nearly the same pore size of 3–4 nanometers.”
More accessible and affordable
Developed at the KTH Division of Micro and Nanosystems , the findings bring sophisticated molecular analysis a step closer to everyday clinical use, potentially advancing personalized medicine worldwide.
“This could make genetic testing and protein analysis more accessible and affordable, much like how cheaper computer chips made smartphones available to a wider population,” De Ferrari explains.
Contact Fabio De Ferrari for more details.
Scientific article:
Sub-5 nm Silicon Nanopore Sensors: Scalable Fabrication via Self-Limiting Metal-Assisted Chemical Etching , doi: 10.1021/acsami.4c19750
Curious about Fabio's research? Watch interview below
Text: Sturle Hauge Simonsen ( sturle@kth.se )