Transcript
The two most exciting
technologies for extending Moore's law beyond 2020 seem to be graphene
and molybdenite. So we're very pleased to report on research published
in the journal ACS Nano that involves combining graphene and
molybdenite in a very promising, high-performance flash memory
prototype, which also offers advantages in terms of size, flexibility,
and energy consumption.
It was just two years ago that researchers revealed the intriguing
electronic properties of molybdenite, a mineral that is very abundant in
nature. Several months later, they demonstrated the possibility of
building an efficient molybdenite chip.
Now, they've gone further still
by using it to develop a flash memory prototype, a cell that can not
only store data but also maintain it in the absence of electricity. So,
it's well suited to many digital devices such as cameras, phones, laptop
computers, printers, and USB keys.
What's particularly exciting is that the memory prototype combines
the unique electronic properties of molybdenite with graphene's amazing
conductivity. This will lead to a new era in electronics, because
molybdenite and graphene are both expected to surpass the physical
limitations of our current silicon chips and electronic transistors.
Plus, the fact that they're both made up of single-atom thick layers
gives them huge potential for miniaturization and mechanical
flexibility.
Although graphene is a better conductor, molybdenite has more
advantageous semi-conducting properties. Specifically, molybdenite has
an ideal "energy band" in its electronic structure that graphene does
not. This allows it to switch very easily between its "on" to an "off"
states, and thus to use less electricity. Used together, the two
materials can combine their unique advantages.
The transistor prototype used in the flash memory was designed using
"field effect" geometry, which is a bit like a sandwich. In the middle,
instead of silicon, a thin layer of molybdenite channels electrons.
Underneath, the electrodes transmitting electricity to the molybdenite
layer are made out of graphene. And on top, the scientists also included
an element made up of several layers of graphene, which captures
electric charge and thus stores memory.
Combining these two materials enabled the researchers to make great
progress in miniaturization. And using these transistors also opens the
door to creating flexible nanoelectronic devices.
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