High-voltage stability coatings in the Zeus panel

A high voltage is applied to the screen spacer of the Zeus panel to obtain high brightness and long phosphor lifetime. To prevent field emission due to high local field strength, the screen spacer is coated with a resistivity layer and a low secondary-electron-emission layer. Efficiently operating panels have been made with sputtered substoichiometric and stoichiometric silicon nitride films, and with sprayed chromium oxide and silicon nitride particle layers. For the sputtered layers the effect of stoichiometry, sheet resistance and layer thickness on the panel performance is discussed. In the case of the sprayed layers the effect of suspension quality, spray conditions, layer thickness and layer roughness is discussed.