Abstract: Pellicles of p-xylylene polymer of non-uniform thickness are prepared between a plurality of mold plates having planar or contoured mold surfaces by positioning the mold surfaces apart with respect to each other so as to form a passage therebetween, and, while providing a pattern of non-uniform pressure between, and/or temperature on, the mold surfaces, directing a stream of vapors of p-xylylene monomer through such passage so as to cause the monomer to condense and polymerize on the mold surfaces in a non-uniform manner in response to such pattern of pressure and/or temperature.The mold plates are held stationary, and/or are rotated, in the vapor condensation zone, during the pellicle forming operation.

Abstract: Pellicles of para-xylylene polymers are used as the sole support media for masses of objects supported thereon. The supported objects can be combined with the pellicle either during the formation of the pellicle or after the pellicle has been manufactured. The composite article is used wherever it is desirable to provide a support media which has as little detrimental influence as possible on the intended function of the supported object.