Flexible display device such as a flexible organic light emitting display, flexible liquid crystals etc are developed. Prevention of moisture formation on the film of plastic material is of utmost importance. The nitride film formed by the ion beam prepared by us is most suited for the above purpose. The technique of ion sputtering that enables the formation of a fine film at a low temperature is the most suited technique for this purpose. The Roll to Roll process is essential for acquiring productivity in case of flexible substrate. We have started a trial production of the equipment mentioned below for a trial run from our customers. We have made provisions in such a way that all our customers can participate in the trial run.