Role of Negative Electric Field Biasing on Growth of Vertically Aligned Carbon Nanotubes Using Chemical Vapor Deposition

Abstract

A new method of manufacturing Mollenstedt electron spectrometer entrance slits is described. The new slits have radically improved performance and service life.

Discharge characteristics of a nano-sized electrode with aligned carbon nanotubes grown on a tungsten whisker tip under various gas conditions

“…First, nickel (Ni) particles were deposited as a catalyst on the apex of the W whisker by RF magnetron plasma processing (100 W net power) for 40 s. The multiwalled carbon nanotubes (MWCNTs) were grown by chemical vapour deposition (CVD) on the W whisker substrate [14,15]. After 10 min of pretreatment by ammonia (NH 3 ) gas, the CNTs' growth process was performed for 5-15 min under the following conditions: the gas flow rates of NH 3 and C 2 H 2 were 150 sccm and 50 sccm, respectively, the pressure was fixed at 30 Torr and the stage heating temperature was 900 • C. A key point in obtaining vertically aligned CNTs is applying a dc voltage during the growth process [16]. In our experiment −100 V dc was applied between the whisker and a Ti mesh situated at a distance of approximately 2 mm.…”

Plasma Enhanced Chemical Vapour Deposition of Horizontally Aligned Carbon Nanotubes

“…The global electric fields lie somewhere between 0.1 and 0.5 V/µm. The combined findings of [19,20,47,48] indicate that an electric field in the range of 0.1–2.0 V/µm is necessary to achieve alignment, values that are consistent with these extremities. Note, also, that Jang et al [21] reported negligible improvements in the alignment “quality” for fields >2.0 V/µm, whilst Ural et al [19] found an optimal field of 0.1 V/µm.…”

Positioning Pd catalyst particles for carbon nanotube growth using charge patterns created with a scanning electron microscope

“…Here, the Pd nanoparticles act as catalyst for carbon nanotube growth. 6,7 In Fig. 3 the total experimental procedure is schematically shown.…”

“…In this article, we report the use of this technique for the growth of carbon nanotubes from palladium catalyst particles 6 on an electrically insulating surface. 7 We shall first discuss the basic principle of defining charge patterns in an insulator with a finely focused electron beam, the basic working of the glowing wire generator and the deposition of charged nanoparticles, and finally the results of carbon nanotube growth on predefined positions.…”