A material source evaporator for use with an evacuable interior deposition chamber in which evaporated materials are deposited on substrates comprising a container with an associated heater that can heat an vaporizable material provided in the container to provide a vapor thereof. A manifold having a plurality of output apertures also has an associated heater that can heat the material vapor provided in the manifold to remain sufficiently vaporous to pass out of output apertures which are in a selected pattern to provide a calibrated spatial distribution of material vapor that results in a deposition thereof in a layer on an adjacent substrate in a fixed position. Thus, the layer has a relatively uniform thickness.