A Comparative Study of Three Different Chemical Vapor Deposition Techniques of Carbon Nanotube Growth on Diamond Films

Betty T Quinton,Sharmila M Mukhopadhyay,Jack Burke,Paul N Barnes,Bang-Hung Tsao,Kevin J Yost,Chakrapani V Varanasi

doi:10.1155/2013/356259

Abstract

This paper compares between the methods of growing carbon nanotubes (CNTs) on diamond substrates and evaluates the quality of the CNTs and the interfacial strength. One potential application for these materials is a heat sink/spreader for high-power electronic devices. The CNTs and diamond substrates have a significantly higher specific thermal conductivity than traditional heat sink/spreader materials making them good replacement candidates. Only limited research has been performed on these CNT/diamond structures and their suitability of different growth methods. This study investigates three potential chemical vapor deposition (CVD) techniques for growing CNTs on diamond: thermal CVD (T-CVD), microwave plasma-enhanced CVD (MPE-CVD), and floating catalyst thermal CVD (FCT-CVD). Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (TEM) were used to analyze the morphology and topology of the CNTs. Raman spectroscopy was used to assess the quality of the CNTs by determining theID/IGpeak intensity ratios. Additionally, the CNT/diamond samples were sonicated for qualitative comparisons of the durability of the CNT forests. T-CVD provided the largest diameter tubes, with catalysts residing mainly at the CNT/diamond interface. The MPE-CVD process yielded non uniform defective CNTs, and FCT-CVD resulted in the smallest diameter CNTs with catalyst particles imbedded throughout the length of the nanotubes.

Highlights

Carbon nanotubes (CNTs) are lightweight materials that express superior mechanical, electrical, and thermal properties [1,2,3,4]
The peaks found around 1350–1365 cm−1 are called disorder peak (D-peak), resulting from the disorderly network of sp2 and sp3 carbon clusters, whereas the peaks found around 1580–1620 cm−1 are called graphite peak (G-peak) as a result of graphite, and the peak found at 1332 cm−1 is the diamond peak [30,31,32]
The optical images after the sonication test were unchanged for T-chemical vapor deposition (CVD) and floating catalyst thermal CVD (FCT-CVD) which are represented by Figure 8(d) top image

Summary

Introduction

Carbon nanotubes (CNTs) are lightweight materials that express superior mechanical, electrical, and thermal properties [1,2,3,4]. Successful CNT growth on a diamond substrate creates a unique all-carbon structure that can be beneficial for advanced power and electronic applications. Various methods such as chemical vapor deposition (CVD), laser ablation, thermal evaporation, arc discharge, and glow discharge have been used to grow CNTs on different surfaces [7,8,9] including diamond substrates and nanoparticles [9,10,11]. Among these methods, CVD is perhaps the most promising and scalable approach for future power and electronic devices. Catalyst and substrate interactions can create differences in root growth or tip growth mechanisms, size distribution, and defects in CNTs growth [12,13,14]

Methods

Results

Conclusion