title: High frequency scanning gate microscopy and local memory effect of carbon nanotube transistors.
abstract: We use impedance spectroscopy to measure the high-frequency properties of single-walled carbon nanotube field effect transistors (swCN-FETs). Furthermore, we extend scanning gate microscopy (SGM) to frequencies up to 15 MHz and use it to image changes in the impedance of swCN-FET circuits induced by the SGM tip gate. In contrast to earlier reports, the results of both experiments are consistent with a simple RC parallel circuit model of the swCN-FET, with a time constant of 0.3 micros. We also use the SGM tip to show the local nature of the memory effect normally observed in swCN-FETs, implying that nanotube-based memory cells can be miniaturized to dimensions of the order of tens of nm.
authors.affiliation: Department of Physics and Astronomy and Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Cristian
authors.initials: C
authors.lastname: Staii
authors.forename: Alan T
authors.initials: AT
authors.lastname: Johnson
authors.forename: Rui
authors.initials: R
authors.lastname: Shao
authors.forename: Dawn A
authors.initials: DA
authors.lastname: Bonnell
mesh_terms: D017097:Electric Impedance; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D016247:Information Storage and Retrieval / Q000379:methods*; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D037742:Nanotubes, Carbon / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure*; D014173:Transistors, Electronic
chemical_list: D037742:Nanotubes, Carbon