Getting a graphene-based transistor to turn on and off has typically meant sacrificing its incredible electron mobility in the bargain. And the truth of it is that graphene's electron mobility—which is 200 times greater than that of silicon—is what has made it such an attractive alternative in a post silicon world.
Lately, research has been focused on coming up with different varieties of graphene better suited to electronics applications. A so-called “graphene monoxide (GMO)” looks promising, and an isotopically engineered graphene could find use in heat management applications for electronics.
Researchers at the Samsung Advanced Institute of Technology have taken a different approach. Instead of altering the graphene, they have re-engineered the basic operating principles of digital switches.
They developed a three-terminal active device (described in the journal Science) in which the key feature is a “an atomically sharp interface between graphene and hydrogenated silicon.” The device, capable of switching on and off via a Schottky barrier that controls the flow of current by changing its height, does so without the graphene losing any of its precious electron mobility.
Whenever you demonstrate a transistor, you get the usual refrain of: “Let me know when you make a simple logic circuit.” Ask and it shall be given. The Samsung researchers have reported the most basic logic gate (inverter) and logic circuits (half-adder) as part of their research, and demonstrated a basic operation (adding).
With nine patents already filed around this research, maybe this will be the way forward in bringing graphene to commercial electronics.