Surface Potential of Phosphor Under Low Energy Electron Irradiation
Details
The surface potential of ZnS : Ag, Cl phosphor coated with In_2O_3 conducting layer under low energy electron excitation was investigated. The mesh electrode was fabricated on the phosphor sample, then, mesh and sample currents were measured a s a function of mesh voltage. The mesh and sample currents changed abruptly at mesh voltage corresponding to the surface potential. The surface potential changed according with the weight of In[OCH(CH_3)_2]_3. It is suggested that the pronounced charging-up occurs at the excitation voltage lower than 200V in ZnS : Ag, Cl phosphor. It should be emphasized that this method was very effective for the measurement of surface potential. Moreover, the incident electron energy was increased with respect to the coating ratio. It indicated that the resistivity of the phosphor surface decreased by the coating process.
