Field Emission Characteristics of Semiconductor Cathodes

A metal-oxide-semiconductor (MOS) electron tunneling cathode using n-and heavily doped p-type Si substrates were fabricated and their characteristics were measured. Two energy peaks in the energy distributions of emitted electrons from the n-type and the p-type cathodes were observed. The paper discuses the experimental results to clear an emission mechanism from a semiconductor cathode and shows that a part of electrons are emitted into vacuum from the valence band of Si substrate by tunneling through the oxide barrier. In addition, the paper discusses a functional cathode with high emission efficiency and low energy dispersion based on a concept of energy band engineering of semiconductor.