Today's commercial flash memories usually store data as electric charge in polysilicon layers. Because polysilicon is a single continuous material, defects in the material can interfere with the desired charge movement, which can limit data retention and density.
To overcome this problem, researchers have recently been working on storing charge in discrete charge traps, such as nanocrystals, instead of polysilicon layers. Since discrete charge trap materials have the advantage of preventing unwanted charge movement as a result of their lower sensitivity to local defects, they offer the potential for high-density flash memories.
Now in a new study, scientists have used graphene quantum dots instead of nanocrystals as the discrete charge trap material. The researchers, Soong Sin Joo, et al., at Kyung Hee University and Samsung Electronics, both in Yongin, South Korea, have published their paper on graphene quantum dot flash memories in a recent issue of Nanotechnology.