| abstract |
Appts. includes several evaporators, which are heated to below the b.pts. of the materials being evaporated. Working surface of each evaporator is fed with a dose of a material, and the dose is completely evaporated in a time (T). Evaporators are fed with doses of materials in the time sequence T/n, where n is the number of evaporators. Pref. appts. includes a rotary doser contg. recesses located at 360 degrees/n intervals round a rotating shaft. Homogeneous deposits, e.g. of arsenic sulphide and/or selenide, can be obtd. on wide, flexible strip or foil fed continuously through the appts. |