Carbon-nanotube electron emitters for display applications

Abstract

Abstract— The optoelectronic, mechanical, and thermal properties of carbon nanotubes have made them very attractive for a wide range of potential applications. However, many applications require the growth of aligned/micropatterned carbon nanotubes with or without a modified nanotube surface. We have developed several simple pyrolytic methods for large‐scale production of aligned carbon‐nanotube arrays perpendicular to the substrate surface. We have also used photolithographic and soft‐lithographic techniques to pattern our aligned carbon nanotubes with submicron resolution. These aligned carbon‐nanotube arrays can be transferred onto various substrates of particular interest (e.g., on conducting substrates as electron emitters for flat‐panel displays) in either a patterned or non‐patterned fashion. The well‐aligned structure further allows us to prepare aligned coaxial nanowires of carbon nanotubes sheathed with polymers and to modify the surface of individual carbon nanotubes by plasma treatment. These aligned/micropatterned carbon nanotubes with and without surface modification possess desirable properties for electron emission applications.

Controlled partial embedding of carbon nanotubes within flexible transparent layers

“…Inversion of the as-grown CNTs, which is inherent in our method, may have additional benefits, since it is well known that CNTs grown on a surface typically have closed ends at their tips and potentially also catalyst particles there [14]. For applications such as field emission and sensing, open ends are preferable [15], which inversion may provide.…”

Controlled preparation and electron emission properties of three-dimensional micropatterned aligned carbon nanotubes

“…In view of the above peculiar emission behavior of the 3D micropatterned ACNTs and our earlier results of a fieldenhanced emission current and reduced turn-on voltage for electron emitters based on nonpatterned plasma-polymercoated ACNT arrays, 28,29 we moved one step further in this study to test if the stepwise emission seen above could also be introduced by patterned plasma modification of the ACNT emitters while retaining their uniform height. The plasma patterned ACNT array was performed on an as-synthesized FePc-generated ACNT array by plasma polymerization of hexane with the monomer pressure of 0.25 Torr at 250 kHz and 30 W for 90 s through the hexagonal TEM grid.…”