Design, Synthesis and Characterization of Vertically Aligned Carbon Nanotubes (VACNTs) on SiC for Enhanced Field Emission
Abstract
The use of carbon nanotubes (CNTs) as field electron emitters has garnered attention due to their high aspect ratio, mechanical strength, and thermal stability. However, challenges such as vertical alignment, catalyst impurities, contact resistance, adherence to substrates, and controlled growth methods hinder their application in high-power field emission (FE) devices. Catalyst impurities, in many cases metallic particles, cause unreliable electron emission response, can reduce electron emission density, and can also be responsible for other undesirable side effects; either by melting and or evaporation of catalyst. In addition, bonding of CNT to any substrate is a formidable task since carbon does not wet and bond to other materials easily. As a result of this intrinsic properties of carbon, the bond strength between CNT and substrates is weak causing two engineering challenges. First, weak interface between CNT and substrate increases electrical resistance at the interface. Second, equally importantly, weak interface creates heat spike at high power applications which is a significant challenge in pulsed power conditions. To overcome these challenges, this project proposal aims to investigate the controlled formation mechanism of catalyst-free vertically aligned CNTs (VACNTs) on ultra-wide band gap silicon carbide (SiC) substrates through vacuum decomposition and evaluate their field emission performance for pulsed power applications in collaboration with the US Air Force Laboratory (AFRL). This research proposal encompasses four primary objectives- (1) Understanding the controlled fabrication of VACNTs on SiC; (2) Exploring the relationship between the height and structure of VACNTs and their electrical and thermal properties and field emission (FE) performance; (3) Understanding the relationship between CNT morphology and FE performance; (3) Demonstrating the feasibility of large area VACNT-SiC.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2024
- Source ID
- FA95502310593
Entities
People
- Göknur Cambaz Büke
Organizations
- Air Force Office of Scientific Research
- TOBB University of Economics and Technology
- United States Air Force