In this work, we have fabricated a triode field emitter using directly grown carbon nanotubes (CNTs) as an electron emission source. Vertically aligned CNTs have been grown in the centre of the gate hole, to the size of 1.5 μm in diameter, using thermal chemical vapour deposition. A comparison of the field emission characteristics of two types of microgated nanotube emitter with and without a sidewall protector for the gate hole is made. A sidewall protector formed by the method of tilting the substrate can enhance the electrical characteristics by suppressing the problem of short circuits between the gate and the CNTs. The leakage current of an emitter with a sidewall protector is approximately sevenfold lower than that of an emitter without a sidewall protector at a gate voltage of 100 V.
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering