A team of Northwestern researchers recently brought technology a step closer to shrinking computer chips to the size of molecules.

The team, led by material sciences Assistant Prof. Mark Hersam, was the first to align two molecules on a room-temperature silicon surface. The findings, published in the Sept. 27 issue of Applied Physics Letters, can be applied to molecular electronics.

Over the past few decades, the “relentless miniaturization” of silicon microelectronics has resulted in a steady reduction in the size of electronic devices, Hersam said. But today’s silicon chips can only shrink so much, and nanotechnology — which operates on the molecular level — is the next step, said Rajiv Basu, a fourth-year graduate student and co-author of the team’s paper.

That’s where the research comes in.

“What we’ve been interested in doing is taking this to the ultimate limit, to make the electronic devices as small as possible,” Hersam said.

Scientists previously were able only to combine different molecules after freezing them.

Now the team will begin studying the fundamental properties of their new structure, Basu said. Researchers with a comprehensive understanding of the shapes and characteristics of different nanostructures will be able to “scale up” the team’s results and build a tinier computer in the future, Basu added.

“We can show how to build one structure like this, but in order to make a molecular computer one would have to make millions of structures in a very controlled way,” he said.

The team’s findings will help others create different combinations of molecules, Hersam said.

“(The process) should work with a wide range of molecules,” Hersam said. “The two we chose are interesting, and we will certainly study them, but we will study many, many more in the future.”

Reach Tina Peng at [email protected].