X-ray induced modification of electronic properties of boron nitride thin films

X-ray induced modification of the electronic properties of nanocrystalline boron nitride (BN) films with different compositions and carbon impurity contents is reported. The related changes of the surface composition and valence band structures of the irradiated films are discussed. X-ray irradiation of nanocrystalline BN films is shown to widen areas with intermediate values of electroconductivity (associated with areas of high emission density) and to increase the average value of electroconductivity by redistributing surface potentials and electron emission sites. Improvement of the field emission is observed with both increasing electron current and diminishing thresholds. Longer x-ray irradiation times yield greater improvement.