Cleaning of a pellicle-mask assembly

摘要

A main objective of the present invention is to provide a method of making a foreign matter harmless which can make the foreign matter, after attaching a pellicle, existing on a transmitting region of a reticle with a pellicle harmless, under pellicle attached condition. For attaining the above-described objective, the present invention provides a method of making a foreign matter harmless wherein a foreign matter existing on a transmitting region of a reticle with a pellicle is irradiated with laser, via the pellicle membrane to make the foreign matter harmless.