Enhanced field emission density current of a planar triode structure with double cathodes

Field emission properties of a planar triode structure with double cathodes have been investigated. ZnO nanotetrapod emitters mixed with carbon nanotubes(CNTs) were fabricated by the screen-printing method. The potential distribution, electron trajectoryies distribution and current density distribution were simulated in detail with CST PARTICLE STUDIO code. A higher field emission density current was obtained in the double-cathode structure. We found the gate played an important role in the anode current enhancement by focusing effect.