Laser Mask Repair for Advanced Technologies

Abstract:
The repair of advanced technology photomasks, using a deep ultraviolet (DUV) wavelength ultra-short femtosecond pulse time laser tool, has been proven highly effective for mask house production. This repair system uses high numerical aperture DUV microscope optics to resolve nano-scale patterns and defects on any mask type. It then, using the same objective optics used to image the defect, selectively removes defects from the mask surface with a cold ablation of any absorber material without damaging the optically transmissive substrate. Repair results are demonstrated for critical edge repairs and both large to small area 2D pattern repairs (with relative pattern alignment registration). The system’s high throughput for these repairs is also discussed.