Tunneling controlled field emission of boron nitride nanofilm

Hexagonal polycrystalline boron nitride (BN) films are synthesized on Si substrates by plasma assisted chemical vapor deposition. In the case of the BN films thicker than 20 nm, the turn-on electric field of the electron emission decreases with increasing surface roughness. It is suggested that electron emission occurs due to Fowler–Nordheim tunneling through the surface potential barrier. An introduction of the BN nanofilm is proposed to reduce the operation electric field of the electron emission. The turn-on electric field of 8.3 V/μm is achieved for the BN nanofilm with a thickness of 8–10 nm, the surface roughness of which is almost the same as that of the flat Si substrate. It is demonstrated that an introduction of the BN nanofilm is effective in improving the field emission characteristics.