MIT, Harvard Pattern Graphene with DNA 

There has been a good deal of hype over graphene in the past year, and for good reason—it is both the strongest and most electrically conductive material known to man, and could already be on its way to creating better computer chips and more effective water desalination.

Unfortunately, the material isn't as easy to work with as headlines would suggest. In sheets the material can tear easily, it isn't a semiconductor in its base state, and it is more expensive to work with than its silicon predecessor.

Still, semiconductor giants such as Intel and TSMC haven't been deterred. Their hope, and the hope of others across the computing industry, is that once these obstacles are overcome graphene will deliver computer chips that operate on hundreds of gigahertz at extremely low power costs.

Now, chemical and molecular engineers at MIT and Harvard may have found a way to overcome all of these problems. By using templates made of DNA, the scientists have successfully patterned graphene into nanoscale structures, making graphene easier to work with and thus turn into a semiconductor for a computer chip.

Last year, Harvard's Wyss Institute laid the groundwork for this project with a technique that cold build DNA “Lego bricks” out of intricate DNA nanostructures. The bricks are made of DNA strands that bind to one another at 90-degree angles. Once enough bricks are joined together, the researchers were able to build 102 distinct 3D shapes.

Now, MIT and Harvard researchers are taking a molecule called aminopyrine to bind these shapes to a graphene surface. The DNA is stabilized through coatings of silver and gold, which in turn serves as a mask for the plasma lithography process. There, any uncovered graphene is stripped away by oxygen plasma. Finally, the DNA mask is removed with sodium cyanide, leaving only a graphene cast from the DNA mold.

So far the process, called metallized DNA nanolithography, has created X and Y junctions, rings and ribbons with the graphene. The rings and ribbons are of particular importance, as they can then be used as quantum interference transistors and semiconductors within computer chips. The details of this research was published this past week in Nature Communications.

Full story at ExtremeTech