Process flow and pellicle type for 157 nm mask making

A method for forming a photomask and pellicle suitable for use in photolithography with incident electromagnetic radiation in a wavelength range from above 250 nm to below 150 nm. The opaque regions of the photomask are formed directly within a transparent F-doped quartz layer by either gallium ion staining using a focused ion beam (FIB) or by deposition of carbon atoms within trenches formed in the transparent layer, said carbon atom deposition being a result of the interaction of a FIB with styrene molecules. An alignment boundary formed on the resulting mask allows a hard pellicle to be fit directly over it so as to avoid warping.