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arXiv · 1303.6603

Molecular Memory with Atomically-Smooth Graphene Contacts

Ahmad Umair·Tehseen Z. Raza·Hassan Raza
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Abstract

We report the use of bilayer graphene as an atomically-smooth contact for nanoscale devices. A two-terminal Bucky ball (C60) based molecular memory is fabricated with bilayer graphene as a contact on the polycrystalline nickel electrode. Graphene provides an atomically-smooth covering over an otherwise rough metal surface. The use of graphene additionally prohibits the electromigration of nickel atoms into the C60 layer. The devices exhibit a low-resistance state in the first sweep cycle and irreversibly switch to a high resistance state at 0.8-1.2 V bias. The reverse sweep has a hysteresis behavior as well. In the subsequent cycles, the devices retain the high-resistance state, thus making it write-once read-many memory (WORM). The ratio of current in low-resistance to high-resistance state is lying in 20-40 range for various devices with excellent retention characteristics. Control sample without the bilayer graphene shows random hysteresis and switching.

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Ahmad Umair, Tehseen Z. Raza, Hassan Raza. 2013-03-26. Molecular Memory with Atomically-Smooth Graphene Contacts. https://doi.org/10.1186/1556-276x-8-476

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