Method for the preparation of a frame-supported pellicle for photolithography

摘要

An improvement is proposed in the method for the preparation of a frame-supported pellicle involving a step in which a resin film for the pellicle membrane formed on the surface of a substrate plate by the solution casting method is adhesively bonded to a rigid pellicle frame and then the substrate plate is removed by separating from the resin film by pulling the substrate and the frame apart in a gaseous atmosphere of which the relative humidity is 80% or higher in contrast to the conventional procedures in which this step is conducted either in water or in a gaseous atmosphere of an air-conditioned clean room having a relative humidity never exceeding 60%. By virtue of this unique procedure, an outstandingly small number of dust particles are deposited on the pellicle membrane obtained by the removal of the substrate therefrom along with an advantage of very smooth and easy removal of the substrate not to cause slack or rupture of the membrane.