| AVS 58th Annual International Symposium and Exhibition | |
| Thin Film Division | Wednesday Sessions |
| Session TF2+EM-WeA |
| Session: | Nanostructuring Thin Films |
| Presenter: | Ryan Pearce, North Carolina State University |
| Authors: | R.C. Pearce, North Carolina State University A.W. Vasenkov, CFD Research Corporation D.K. Hensley, Oak Ridge National Laboratory M.L. Simpson, Oak Ridge National Laboratory T.E. McKnight, Oak Ridge National Laboratory A.V. Melechko, North Carolina State University |
| Correspondent: | Click to Email |
A key factor to the implementation of vertically aligned carbon nanofibers (VACNFs) in devices is a more fundamental understanding of how to control fluctuations in the growth direction of the fibers. It has previously been hypothesized that the electric field is the primary factor in determining the orientation of fibers grown catalytically using plasma enhanced chemical vapor deposition (PECVD). Here we present results of carbon nanofiber synthesis on insulating substrates by dc plasma in the vicinity of grid electrodes. To perform these observations, VACNFS were synthesized on a fused silica substrate using direct current PECVD. To maintain continuous glow discharge above the substrate, a metal grid electrode layer (Cr) was deposited over silica with windows of exposed silica ranging in size from 200 µm to 1 mm. Observed trends in nanofiber alignment at the window-electrode interface suggests that the alignment is governed by the direction of the ion flux rather than the electric field at the substrate level. The proposed alignment mechanism is that ion sputtering of the carbon film on a catalyst particle the growth direction of the nanofibers. With this development, fiber growth direction can be better manipulated through changes in ionic flux direction, opening the possibility for growth of nanofibers on substrates with unique geometries.