In this work, we report a direct growth of the VACNTs on several substrates by using hot-filament chemical vapor deposition (hot-filament CVD) and a catalytic buffer-layer structure. The buffer layer was the aluminum (Al) thin film used together with iron (Fe) as the catalyst. | VNU Journal of Science Mathematics Physics Vol. 36 No. 2 2020 98-105 Original Article Hot-filament CVD Growth of Vertically-aligned Carbon Nanotubes on Support Materials for Field Electron Emitters Nguyen Thanh Hai Dang Nhat Minh Do Nhat Minh Nguyen Dinh Dung Luong Nhu Hai Phan Ngoc Hong Nguyen Tuan Hong Center for High Technology Development Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Hanoi Vietnam Received 03 March 2020 Revised 11 April 2020 Accepted 06 April 2020 Abstract Carbon nanotubes are used in different applications such as energy storages electronic devices. For these applications a direct assembly of the vertically-aligned carbon nanotubes VACNTs on electrically conducting substrates is of interest. In this work we report a direct growth of the VACNTs on several substrates by using hot-filament chemical vapor deposition hot-filament CVD and a catalytic buffer-layer structure. The buffer layer was the aluminum Al thin film used together with iron Fe as the catalyst. It was found that the Al underneath layer was necessary for obtaining the VACNT forests with high purity and good contact. The as-fabricated VACNT support-material structures are of the object to test field electron emission properties. Characterization results of the VACNT samples demonstrated a promising application for the field emission in terms of the high emitting currents. Keywords Carbon nanotubes hot-filament CVD field electron emission catalysis. 1. Introduction Carbon nanotubes have potential applications including interconnects for supercapacitors fuel cells electron emitting devices 1-5 . For these applications a direct assembly of the vertically-aligned carbon nanotubes VACNTs on electrically conducting substrates is mostly needed. The most obvious method to obtain such structures is the direct growth of the carbon nanotubes on conducting substrates. In recent years the VACNT synthesis has significantly advanced. Key points have been attributed to not only .
