Defect Repair Techniques For X-Ray Masks

Low defect density masks are necessary to obtain the high chip yields required in VLSI technology. This paper will outline the boron nitride mask fabrication process that has been developed at AT&T Bell Laboratories, and discuss the nature and distribution of normally encountered defects. The advantages and disadvantages of various repair techniques will be addressed and specific examples of repairs made on silicon integrated circuit X-ray masks will be shown.