Polycrystalline Diamond, Boron Nitride and Carbon Nitride Thin Film Cold Cathodes

Abstract

ABSTRACTRecent observations are presented on the emission of electrons from n-type polycrystalline diamond and from two new families of nitride-based cold cathode films, n-type boron nitride (BN) and n-type carbon nitride (CN). The n-type polycrystalline diamond films were synthesized by MPECVD. The BN and CN n-type films (∼150 nm) were synthesized by reactive laser ablation on n-type polycrystalline diamond (∼24 μm) on (100)Si.Emission current densities have been measured as high as 119 ma cm−2. Extraction fields have been observed to range from ∼0 V μm−1 up. The diamond films show a field activated thermionic behavior. Both the BN and the CN films show a power-law current density / applied field response implying a negative electron affinity (NEA) type behavior.