Controlling the Structure of Aligned Carbon Nanotubes on Silicon-Carbide Wafers

Author(s):  
Michiko Kusunoki ◽  
Toshiyuki Suzuki ◽  
Chizuru Honjo ◽  
Tsukasa Hirayama
2006 ◽  
Vol 527-529 ◽  
pp. 1579-1582 ◽  
Author(s):  
John Boeckl ◽  
W.C. Mitchel ◽  
Wei Jie Lu ◽  
J. Rigueur

Aligned carbon nanotubes (CNT’s) are formed on the surface of silicon carbide (SiC) wafers during high temperature anneals. The exposed 4H SiC surface transforms into CNT’s for temperatures in the range of 1400-1700°C and under moderate vacuum conditions (10-2 – 10-5 torr). The rate of formation on the C-face (0001,‾) is about three times the rate on the Si-face (0001), but both rates increase with anneal temperature. SEM, TEM and Raman scattering measurements have confirmed the presence of both single-wall and multi-wall CNT’s. The carbon source is believed to be residual carbon from the SiC left on the surface after preferential evaporation of Si. CNT formation is believed to be catalyzed by low concentrations of residual oxygen in the chamber. Subsequent I-V measurements provide insight into the electrical characteristics of the CNT’s and the SiC/CNT interface.


2003 ◽  
Vol 772 ◽  
Author(s):  
Masakazu Muroyama ◽  
Kazuto Kimura ◽  
Takao Yagi ◽  
Ichiro Saito

AbstractA carbon nanotube triode using Helicon Plasma-enhanced CVD with electroplated NiCo catalyst has been successfully fabricated. Isolated NiCo based metal catalyst was deposited at the bottom of the cathode wells by electroplating methods to control the density of carbon nanotubes and also reduce the activation energy of its growth. Helicon Plasma-enhanced CVD (HPECVD) has been used to deposit nanotubes at 400°C. Vertically aligned carbon nanotubes were then grown selectively on the electroplated Ni catalyst. Field emission measurements were performed with a triode structure. At a cathode to anode gap of 1.1mm, the turn on voltage for the gate was 170V.


2019 ◽  
Author(s):  
Mingguang Chen ◽  
Wangxiang Li ◽  
Anshuman Kumar ◽  
Guanghui Li ◽  
Mikhail Itkis ◽  
...  

<p>Interconnecting the surfaces of nanomaterials without compromising their outstanding mechanical, thermal, and electronic properties is critical in the design of advanced bulk structures that still preserve the novel properties of their nanoscale constituents. As such, bridging the p-conjugated carbon surfaces of single-walled carbon nanotubes (SWNTs) has special implications in next-generation electronics. This study presents a rational path towards improvement of the electrical transport in aligned semiconducting SWNT films by deposition of metal atoms. The formation of conducting Cr-mediated pathways between the parallel SWNTs increases the transverse (intertube) conductance, while having negligible effect on the parallel (intratube) transport. In contrast, doping with Li has a predominant effect on the intratube electrical transport of aligned SWNT films. Large-scale first-principles calculations of electrical transport on aligned SWNTs show good agreement with the experimental electrical measurements and provide insight into the changes that different metal atoms exert on the density of states near the Fermi level of the SWNTs and the formation of transport channels. </p>


2013 ◽  
Vol 3 (2) ◽  
pp. 155-165 ◽  
Author(s):  
Teresa C.O. Marsi ◽  
Marcus A.F. Corat ◽  
Mirian M. Machado ◽  
Evaldo J. Corat ◽  
Fernanda R. Marciano ◽  
...  

2019 ◽  
Vol 9 (20) ◽  
pp. 4388 ◽  
Author(s):  
Artyom Plyushch ◽  
Jan Macutkevič ◽  
Polina Kuzhir ◽  
Aliaksei Sokal ◽  
Konstantin Lapko ◽  
...  

Hybrid composite materials based on an aluminium phosphate matrix with silicon carbide whiskers and multi-walled carbon nanotubes were studied in a wide frequency range (20 Hz to 36 GHz). It was demonstrated, that the addition of the silicon carbide whiskers enhances the dielectric permittivity and conductivity. This was explained by the difference in tunnelling parameters. Hybrid ceramics with nanotubes and whiskers also exhibits substantially improved electromagnetic shielding properties. The hybrid ceramics with 10 wt. % silicon carbide whiskers and a 1 mm thick 1.5 wt. % carbon nanotube layer, show higher than 50% absorption of electromagnetic radiation.


Carbon ◽  
2014 ◽  
Vol 67 ◽  
pp. 38-47 ◽  
Author(s):  
Huaiyuan Wang ◽  
Li Chang ◽  
Xiaoshuang Yang ◽  
Lixiang Yuan ◽  
Lin Ye ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document