PURPOSE:To enable the photoelectric surface to be mass-produced at the maximum sensitivity and stably, by vacuum-evaporating a non-metal acting as the photoelectric material onto the photoelectric surface until the output current from a semi-conductor photo sensor shows the value within the range of 70-95% to the initial value, thereafter furthermore by vacuum-evaporating an alkali metal thereonto. CONSTITUTION:In case of forming a photoelectric surface 5, the quantitative control of vacuum-evaporating amount of anitmony is especially improtant in order to obtain the excellent and stable photoelectric conversion sensitivity, therefore in this invention the relative output current is detected by a semiconductor photo sensor 13, then said current is controlled to be 70-95% of the initial value, thus the optimum sensitivity and the stable reproducibility can be enahnced. In particular, if a part of a vacuum enclousure 1 which surrounds the photoelectric surface, that is, an X-ray incident window and the wall of said enclosure 1 around the phtoelectric surface are made of metal, the semiconductor photo sensor 13 is disposed inside this enclosure, then the alkali metal is vacuum-evaporated thereonto, next the predetermined amount of non- metal is further vacuum-evaporated thereonto, so by this process the phtoelectric surface 5 with optimum photoelectric sensitivity can be formed securely and easily.
展开▼
