Evidence for a surface resonance feature in the very low-energy electron spectrum of ZrN

Previous investigations of the low-energy (0-40 eV) electron spectra of Ti and V nitrides have been extended to ZrN. The lowenergy spectra of ZrN films prepared by nitrogen ion implantation contain the corresponding features to those previously observed for TiN and VN. However, the ZrN spectrum is dominated by an extremely large feature at about 3 eV, which has not been previously reported. The amplitude of this peak varies directly with the nitrogen concentration. The peak shape and intensity are sensitive to primary electron beam energy in the range 0.5 to 2.0 keV, but the peak position does not change. The strong dependence of the amplitude of this feature on physisorption of gases and crystallographic orientation suggest that this peak arises from structure in the secondary electron spectrum induced by a surface resonance.