WNx diodes on plasma-treated GaAs surfaces

The formation of WN_x Schottky diodes on GaAs surfaces with various interface conditions was investigated by performing H₂- and N₂-plasma treatments on GaAs surfaces prior to the WN_x film deposition. After annealing at 810 degrees C for 10 min, an improvement in the diode rectifying characteristics was generally observed, resulting from the thermal recovery of the sputtering and plasma-induced damage. The maximum Phi ^I-V=0.76 eV was obtained for the H₂-plasma-treated diodes. Samples with an N₂-plasma-treated interface showed a reduced barrier height and a higher ideality factor with corresponding nonlinearity in the C-V curves due to the presence of a high density of interfacial states.