Haze generation effect by pellicle and packing box on photomask

ArF exposure tool have been implementing as a main work force of lithography. And haze generation by high actinic wavelength energy is big issue to be resolved. Many studies have been reported to remove or minimized ion residual on photomask surface and PKL developed haze free process. Even though the surface of photomask is free from ions generating haze defect by haze free process, but the ions from environment like pellicle and packing box make worsen to keep cleanness of photomask. The evaluation of environment effect like outgas from pellicle and packing box have been reported, but it was hard to know pure environmental effect because the surface of photomask was not enough clean to test it. Several pellicles and boxes with different material from supplies were tested in terms of outgas, contamination of ion and threshold energy generating haze. Some material of packing box and pellicle showed very sensitive to keep haze free photomask surface.