Multi-Resolution Imaging of Electron Dynamics in Nanostructure Interfaces
Abstract
This final report describes the development and the application of two novel optoelectronic microscope techniques ( photocurrent imaging and photothermal current imaging ) for studying electron dynamics near the interfaces of electronic devices fabricated based on carbon nanotubes and thin film organic materials, as funded by the AFOSR grant (FA9550-07-1-0338). In carbon nanotube devices, we showed that individual carbon nanotubes can be imaged and characterized using the photothermal current microscopy for the first time. In particular, this technique allows the imaging and electrical characterization of carbon nanotubes one by one even when only one pair of metal electrodes are used to contact all of them. This eliminates the need for individual electrodes for each carbon nanotube, which is time consuming and expensive. With this, the gate dependent electrical conductivity can be measured as well, thus enabling differentiation of metallic carbon nanotubes from semiconducting ones. In pentacene transistors, we used scanning photocurrent microscopy to study spatially resolved photoelectric response of pentacene thin films, which showed that point contacts formed near the hole injection points limit the overall performance of the device. In addition, we estimate the contact resistance of individual contact for the first time, which is of the order of ~1 Gomega per contact point.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 27, 2010
- Accession Number
- ADA564334
Entities
People
- Jiwoong Park
Organizations
- Cornell University