Controlled Growth of Conducting Carbon Nanowires by Ion Irradiation: Electrical and Field Emission properties
- PDF / 1,168,776 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 116 Downloads / 211 Views
1020-GG06-04
Controlled Growth of Conducting Carbon Nanowires by Ion Irradiation: Electrical and Field Emission properties Amit Kumar1, L D Filip2, J. D. Carey2, J. C. Pivin3, A. Tripathi1, and D. K. Avasthi1 Materials Science Group, Inter-Iniversity Accelerator Centre, Aruna Asaf Ali Marg, PB10502, New Delhi, 110067, India 2 ATI, University of Surrey, Guildford, GU2 7XH, United Kingdom 3 CSNSM, Orsay, 91405, France 1
ABSTRACT The conducting carbon nanowires embedded in fullerene matrix are synthesized by high energy heavy ion irradiation of thin fullerene film. We report the control growth of carbon nanowires, their electrical and field emission properties. The typical diameter of the conducting tracks is observed to be about 40 to 100 nm. The conductivity of the conducting zone is about seven orders of magnitude higher than that of the fullerene matrix. The conducting nano wires are evidenced by conducting atomic force microscopy. All the nanowires are parallel to each other and are perpendicular to the substrate. The density (spacing), growth direction and length of these carbon nanowires simply can be changed by ion fluence, angle of irradiation and the film thickness, respectively. The field emission measurements on these nanowires reveal that the threshold voltage is about (~13 V/µm), whereas the as deposited fullerene films shows a break down at (~ 51 V/µm). The present approach of making controlled conducting carbon nanowires is quite promising, as it takes few seconds of ion irradiation and no catalyst is required.
INTRODUCTION The carbon-based materials are expected to be key materials in the future electronics because of their unique characteristics and biocompatibility. The construction of nano-electronic devices is technologically challenging and many different approaches are possible. The controlled growth of a single nanowire or an ensemble of nanowires, their growth direction, suitable alignment and spacing on a substrate is of importance for the applications. The simplification of the nanowire fabrication procedure as well as the development of large scale and low price production methods remains open problems. Ion beam methods are now emerging as a tool in nano-fabrication for structuring material and modification on the nanometer/atomic scale [1-3]. The present paper reports the formation of conducting carbon nanowires by heavy ion irradiation in fullerene films. The effect of the density of energy transferred by ions to target electrons on the dimension and electrical properties of the nanowires are discussed. Their field emission properties are also studied. EXPERIMENTAL DETAILS Fullerene thin films of 200 nm thicknesses were deposited on 50 nm thick Au
layers on Si substrate. Gold films of 50 nm in thickness were deposited on Si substrate by resistive heating. Subsequently, the fullerene films were deposited on these Au films by sublimation of a C60 pellet. A small area of the Au film was masked so that it can be used as a contact for conducting AFM measurement. The X-Ray diffraction patte
Data Loading...
