Samsung Electronics, the world's largest memory chip maker, said Saturday that it has developed a new transistor structure using graphene, or the so-called "miracle material."

According to an e-mailed statement, Samsung Advanced Institute of Technology (SAIT), the tech firm's R&D center, developed a new graphene device for transistor use that can overcome the limits of conventional silicon transistor. The research was published online in the journal Science on Thursday.

Semiconductors consist of billions of silicon transistors. To increase the speed of chips, either the size of the individual transistors have to be reduced to shorten the traveling distance of electrons, or a material with higher electron mobility have to be used to allow for faster electron velocity.

Over the past 40 years, the chip industry reduced the size to boost the chips' performance, but Samsung opened the door to developing the transistor using graphene, which possesses electron mobility about 200 times greater than that of silicon.

Graphene was viewed as a potential substitute, but it cannot switch off electric currents as it is semi-metallic. Both on and off flow of currents is required in a transistor to represent '1' and '0' of digital signals. Previous research tried to convert graphene into a semi-conductor, but this decreased the mobility of graphene rapidly.

Samsung developed a device that can cut off the electric currents in graphene without degrading its mobility by re- engineering the basis operating principles of digital switches. The so-called Schottky barrier can switch electric currents on and off by controlling the height of the barrier.

Samsung said it has solved the most difficult problem in graphene device research and has opened the dor to new directions for future studies. The SAIT now owns 9 major patents related to the structure and the operating method of the graphene device.