Georgia Tech researchers achieve key breakthrough in graphene semiconductors

Researchers at the Georgia Institute of Technology say that the semiconductor of the future may be made from graphene, an arrangement of carbon molecules bonded together in a single sheet, instead of silicon.

The research breakthrough, which was detailed in a paper published last week in the journal Nature, came as the team found a solution to what it described as the last major hurdle to graphene semiconductors – the so-called “band gap” problem. Put simply, the core quality of a semiconductor is the ability to switch it on or off via an electrical current without altering its conductive properties, according to the researchers.

Graphene has long been studied as a possible substitute for silicon, given its very low electrical resistance, which should allow for faster computing, but the band gap issue had not been solved until the team – made up of researchers at Georgia Tech and Tianjin University in China, and led by Georgia Tech professor Walter de Heer – published its latest work.

The team solved the band gap problem by using a technique called electron doping. That involves placing atoms on the graphene that “donate” electrons to the material, which allowed them to manipulate on/off states without damaging the material.

“Our motivation for doing graphene electronics has been there for a long time, and the rest was just making it happen,” de Heer said in a report published by the university. “We had to learn how to treat the material, how to make it better and better, and finally how to measure the properties. That took a very, very long time.”

While de Heer could not be reached for immediate comment, he compared the breakthrough to a “Wright Brothers moment,” in the Georgia Tech report. “They built a plane that could fly 300 feet through the air. But the skeptics asked why the world would need flight when it already had fast trains and boats,” he said. “But they persisted, and it was the beginning of a technology that can take people across oceans.”

The technology is still in its infancy, but the team was eager to talk up its future implications, including its potential applicability to quantum computing, as graphene can allow the quantum mechanical wave properties to be utilized in such systems.