Electron emission from carbon film on island-like tin oxide layer

Electron emission from carbon film on top of island-like tin oxide layer is proposed and demonstrated in this Letter. The tin oxide layer, consisting of regular islands in size of tens of nanometers, induces local heating to the carbon film and helps in forming the electron emission area. Electron emission with good stability and uniformity is reproducibly obtained with emission efficiency up to 1% under an anode voltage of 3 KV applied at 2 mm away.