Diamond junction cold cathode

Abstract Diamond junction cold cathodes composed of a phosphorus doped diamond layer and a boron doped diamond layer have been fabricated and tested. The devices were rectifying and had a large, temperature-dependent series resistance that limited the current when the device was forward biased. Electrons from the device were emitted into the vacuum when the device was forward biased; no emission current was detected from the reverse biased device. The ratio of emitted current to diode current was approximately 10 −8 , the ratio changing little with temperature or bias voltage.