Growth Control of Carbon Nanotube using Various Applied Electric Fields for Electronic Device Applications

Abstract

The control of the growth direction of a carbon nanotube was accomplished by applying an electric field during the growth of the carbon nanotube. The effects of two types of applied bias, one is a constant DC bias, and the other is a ramp bias, on the control of the growth direction were examined. By maintaining a constant DC bias we could control the growth direction of the carbon nanotube, however, the bridging ratio between the two electrodes was as small as 35%. We suppose that this low bridging ratio may be caused by the etching effect of hydrogen. When a ramp bias was applied, bridging ratio tended to increase with the slope of ramp bias. Under optimal conditions, the bridging ratio reached a value as high as 95%.

Controlling Direction of Growth of Carbon Nanotubes on Patterned SiO2Substrate

“…Thus far, only a few studies on the control of the orientation of SWNTs have been reported; [21][22][23][24][25][26][27][28] in these studies, the orientation of SWNTs have been controlled by the application of a strong electric field during the chemical vapor deposition (CVD) growth of SWNTs, [21][22][23][24] gas flow, 25) and the surface orientation of a quartz substrate. [26][27][28] However, these methods have the following drawbacks: [21][22][23][24][25][26][27][28] the application of a strong electric field during the CVD growth of SWNTs requires a complicated wiring structure, [21][22][23][24] the gas flow technique results in the growth of SWNTs only with a unidirectional orientation, 25) and quartz substrates are not suitable for use in conventional silicon processes. [26][27][28] In this study, a new technique to preferentially control the direction of the growth of SWNTs is proposed.…”

CdSe nanowires with controllable growth orientations

“…However, only very few reports on controlled orientation of nanowires of very limited material systems have been demonstrated. 14-20 Yang et al, 14 Maeda et al, 15 and Lee et al 16 realized controlled orientations of carbon nanotubes by applying an electric or a magnetic field on the substrates during growth. Ge et al prepared oriented Si nanowires by thermal evaporation method.…”

Resonance R aman Spectroscopy

“…For the horizontal direction growth, its success has been reported by many groups by using an electric field [43][44][45], a fast gas flow [46,47], and atomic steps of substrates [25,26,48,49,50,51] with other carbon sources. Furthermore, the ACCVD method has not been used for only random or VA-SWNTs, but also for horizontally-aligned SWNTs [52].…”