PURPOSE: To obtain a stable photoelectric screen which changes to a small degree with the passing of time by applying a liquid solution containing the first group matter such as decalin, the second group matter such as naphthalene, and an alkali metal to a base plate coated with an Sb layer, and heating the applied liquid solution so as to evaporate the first and the second group matters.

CONSTITUTION: An Sb layer is formed on the surface of a base plate made of glass, Ni or the like. Next, a matter chosen from among π-electron-system unsaturated hydrocarbon such as naphthalene or diphenyl is dissolved into a solvent chosen from among cyclic hydrocarbons which are liquid at ordinary temperature such as decalin or cyclohexane, and thus prepared solution is added with an alkali metal such as Se, K or Na to make a mixture solution. Then, the mixture solution is applied to the surface of the Sb layer, and heated, for example, at 230°C for 10min so as to evaporate the matters belonging to the first and the second groups. After that, the Sb-alkali matter formed on the base plate is heated and activated in vacuum. As a result, a stable photoelectric screen which changes little with the passing of time can be obtained.