Development of new FIB technology for EUVL mask repair

The next generation EUVL masks beyond hp15nm are difficult to repair for the current repair technologies including focused ion beam (FIB) and electron beam (EB) in view of the minimum repairable size. We developed a new FIB technology to repair EUVL masks. Conventional FIB use gallium ions (Ga+) generated by a liquid metal ion source (LMIS), but the new FIB uses hydrogen ions (H-2(+)) generated by a gas field ion source (GFIS). The minimum reaction area of H-2(+) FIB is theoretically much smaller than that of EB. We investigated the repair performance of H-2(+) FIB. In the concrete, we evaluated image resolution, scan damage, etching rate, material selectivity of etching and actinic image of repaired area. The most important result is that there was no difference between the repaired area and the non-repaired one on actinic images. That result suggests that the H-2(+) GFIS technology is a promising candidate for the solution to repair the next generation EUVL masks beyond hp15nm.