A superaligned
carbon nanotube (SACNT) film can act as an ideal
gate electrode in vacuum electronics due to its low secondary electron
emission, high electron transparency, ultrasmall thickness, highly
uniform electric field, high melting point, and high mechanical strength.
We used a SACNT film as the gate electrode in a thermionic emission
electron tube and field emission display prototype. The SACNT film
gate in a thermionic emission electron tube shows a larger amplification
factor. A triode tube with the SACNT film gate is used in an audio
amplification circuit. The SACNT film gate electrode in field emission
devices shows better field uniformity. The field emission display
prototype is demonstrated to dynamically display Chinese characters.