Skip to Content

Gold Standard

Nanotech

As researchers engineer everything from computer chips to drug-discovery tools down to smaller and smaller scales, making these devices is becoming excruciatingly difficult. The principal micromanufacturing technique, photolithography, uses light to etch microscopic features onto a silicon surface; but it’s expensive and exacting. One promising alternative is called “soft lithography,” a technique that uses flexible rubber stamps to fabricate devices with micro- and nanoscale features.

Until now soft lithography has mainly been used to make tiny devices like microfluidic chambers used for biological research. But Harvard University chemists George Whitesides -soft lithography’s pioneer-and Heiko Jacobs have found a new application: transferring nanoscale patterns of electrical charge onto electrically conductive polymers. This advance could mean a cheaper and easier way to manufacture very small data storage and optical devices.

The Harvard scientists accomplished the trick by first building a mold made of silicon, using traditional photolithography methods to carve out the pattern. They then poured rubbery silicone into the mold to make the stamps, which they coated with a thin layer of gold. When the researchers pressed one of these stamps against a polymer film and ran a current through them, the pattern was transferred to the polymer as a series of positive and negative charges. A single mold can churn out multiple stamps, and each can be used repeatedly.

Although the new technique is now just a lab demonstration, potential new applications include encoding data on charge-based storage devices such as “smart cards”-credit-card-sized pieces of plastic used to verify the cardholder’s identity-or constructing waveguides for optical telecommunications switches. Says Christopher B. Murray, manager of nanoscale materials and devices at IBM’s T. J. Watson Research Center, “This is one more step in a number of beautiful efforts to explore nontraditional patterning technology.”

Keep Reading

Most Popular

Large language models can do jaw-dropping things. But nobody knows exactly why.

And that's a problem. Figuring it out is one of the biggest scientific puzzles of our time and a crucial step towards controlling more powerful future models.

How scientists traced a mysterious covid case back to six toilets

When wastewater surveillance turns into a hunt for a single infected individual, the ethics get tricky.

The problem with plug-in hybrids? Their drivers.

Plug-in hybrids are often sold as a transition to EVs, but new data from Europe shows we’re still underestimating the emissions they produce.

It’s time to retire the term “user”

The proliferation of AI means we need a new word.

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.