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Title: Multizone Rapid Thermal Processing to Overcome Challenges in Carbon Nanotube Manufacturing by Chemical Vapor Deposition
For the scalable production of commercial products based on vertically aligned carbon nanotubes (VACNTs), referred to as CNT forests, key manufacturing challenges must be overcome. In this work, we describe some of the main challenges currently facing CNT forest manufacturing, along with how we address these challenges with our custom-built rapid thermal processing chemical vapor deposition (CVD) reactor. First, the complexity of multistep processes and reaction pathways involved in CNT growth by CVD limits the control on CNT population growth dynamics. Importantly, gas-phase decomposition of hydrocarbons, formation of catalyst particles, and catalytic growth of CNTs are typically coupled. Here, we demonstrated a decoupled recipe with independent control of each step. Second, significant run-to-run variations plague CNT growth by CVD. To improve growth consistency, we designed various measures to remove oxygen-containing molecules from the reactor, including air baking between runs, dynamic pumping down cycles, and low-pressure baking before growth. Third, real-time measurements during growth are needed for process monitoring. We implement in situ height kinetics via videography. The combination of approaches presented here has the potential to transform lab-scale CNT synthesis to robust manufacturing processes.  more » « less
Award ID(s):
1825772
NSF-PAR ID:
10104375
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Manufacturing Science and Engineering
ISSN:
1087-1357
Page Range / eLocation ID:
1
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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