1. Title : Charges and defects in carbon-based electronics

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2. Speaker : Prof. Moonsub Shim

(Department of Materials Science and Engineering, <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />University of Illinois, Urbana )

3. Date : July 5 (Mon), 4:00 P.M. ~

4. Venue : Building 302, Room 509

5. CV :

Ph.D.(2001)   Chemistry, University of Chicago

M.S.(1998)    Chemistry, University of Chicago

B.S. (1997)    Chemistry, University of California at Berkeley

6. Abstract :

From device performance limits to thermal management, understanding charging (e.g. doping), electron-phonon coupling and defect-related processes is fundamentally important in electronics. Due to their atomic thickness, carbon nanotubes and graphene are interesting platforms to examine how local chemical environments affect these fundamental processes. Such studies, in turn, provide effective means of controlling device characteristics. By varying the local chemical environment with different polymers/electrolytes, we show nearly ideal p-n diodes exhibiting promising photovoltaic response from semiconducting nanotubes. In metallic nanotubes and graphene, we elucidate charging and disorder dependent phonon softening effects and electrical characteristics including an unusual resonance in 1/f fluctuations.

7. Contact : Prof. Taeghwan Hyeon (☏880-1873)