Selectively grown Carbon Nanotubes (CNTs): Characterization and field emission properties

These Carbon Nanotubes (CNTs) are considered as one of the promising electron-emitting materials available for use in cold cathode applications such as vacuum microelectronic devices. It has been shown that due to the high aspect ratio (small diameter and relatively long length) it is possible to obtain electron emission at a relatively low applied electric field. Because of this property, CNTs may play an important role when used as cold cathode material in plasma devices. In this work, the experimental results of field emission characteristics of CNTs fabricated using Chemical Vapor Deposition (CVD) are presented. The samples are selectively grown randomly oriented multi-walled CNTs (MWNTs) and synthesize onto plain silicon (n-type 100) substrates. A thin catalyst (Fe) film is first deposited by DC magnetron sputtering and high-quality films of MWNTs are grown in a thermal CVD furnace in a mixture of acetylene and argon gasses, after lithographic lift-off patterning of a metal catalyst layer on the wafer. The measurement results indicate that randomly oriented CNTs have significant field emission capabilities to be used as cold cathode emitters in plasma devices.