19 July 2012
Researchers from Germany and Sweden have developed a new method for creating a transistor from graphene, according to an article at Phys.org.
The headline, “Researchers devise a way to create a graphene transistor,” is a bit misleading. Researchers have been making transistors out of graphene for some time now, and have been using a process based on silicon carbide, like the German-Swedish research.
The real breakthrough for this latest line of research, which was published 17 July in the journal Nature Communications (“Tailoring the graphene/silicon carbide interface for monolithic wafer-scale electronics”), appears to be how they engineered all the constituent parts of the transistor.
To be honest, I am not entirely clear on how even their process diverges drastically from the IBM research. After a year of trying to figure out how to connect all the parts of the graphene-based transistor without damaging it, the IBM team used electron beam lithography and a resist that was sensitive to electrons. The German-Swedish researchers used electron beam lithography too.
Maybe the difference between the two is the use of oxygen plasma etching, which converted the middle channel on the transistor from a contact into a gate. This could be the “tailoring the graphene/silicon carbide interface” of which the paper title speaks.
An important caveat to the research is that because the researchers had to scale up dramatically their transistor they don’t really know how much faster the transistor might be than the current variety. Furthermore, they’re not even sure how fast it might be when they scale the transistor down.
I am sure this work is helpful and evolutionary research in the development of graphene transistors, but I think maybe the Phys.org article has perhaps overstated its case when it says that this research “is the breakthrough computer engineers have been waiting for.”