The conducting charge transfer complex formed on the C60/Cu interface after heat treatment was investigated by using density functional theory. We optimized the geometries of the C60 and C60-Cu complexes. Then, a comparison of the valence band spectrum with the simulated density of states revealed detailed molecular properties. We confirm that the C60-Cu complex layer formed at the C60/Cu interface enhances charge transfer. The conducting complex creates both an occupied gap state and unoccupied states between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of C60. These states lead to the formation of Ohmic contact between the C60 layer and the Cu layer.
Bibliographical noteFunding Information:
This work is supported by BK21 project of the Korea Research Foundation (KRF), the Korea Research Foundation Grant funded by the Korean Government (MOEHRD) (KRF-2005-015-C00130), and the KOSEF through National Core Research Center for Nanomedical Technology.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry