New material for semis said to beat silicon
R Colin Johnson
2/1/2011 11:43 AM EST
PORTLAND, Ore.—A new semiconductor material called molybdenite (MoS2) is claimed to be 100,000 times lower power than silicon, plus will allow the fabrication of much smaller transistors, according to researchers at Switzerland's Ecole Polytechnique Federale de Lausanne (EPGL).
As a next-generation semiconductor material, molybdenite also beats graphene by possessing a bandgap, according the EPGL.
The EPFL claims that molybdenite is an abundant mineral which is already used in steel alloys and as an additive in lubricants. The material is being developed for the first time as a next-generation semiconductor at its EPGL's Laboratory of Nanoscale Electronics and Structures (LANES).
"[Molybdenite] has real potential in the fabrication of very small transistors, light-emitting diodes and solar cells," said EPFL professor Andras Kis.
According to Kis, one or molybdenite's main attributes is that unlike silicon, which is a three-dimensional crystal, molybdenite is an inherently two-dimensional material, permitting thin films as thin as 6.5 angstrom to be relatively easily fabricated (one nanometers equals 10 angstroms) that have an equal electron mobility to two-nanometer thick layers of silicon.
In addition, unlike graphene—which does not possess a bandgap—molybdenite has a bandgap of 1.8 electron-volts, putting it between gallium arsenide (1.4) and gallium nitride (3.4)—opening the possibility of fabricated chips that can handle both electrical and optical functions.
Molybdenite--MoS2--here is used to create an ultra-lower power field effect transistors (FET) by acting as its channel on a silicon-on-insulator substrate using high-k dielectric (HfO2) gate oxide.