Defect dispositioning using mask printability on attenuated phase shift production photomasks

Recently a new mask qualification concept is getting more and more attention. Mask makers are challenged to meet mask and defect specifications of 130 and 100-nm technology node. This means very tight specifications, which usually lead to long mask delivery times. A main factor in the mask making process is mask inspection and repair. The mask repair cycle is not only time-consuming, but also bears the danger of damaging a mask. At the same time, when investigating defect printability, it is getting clear that a lot of today detected defects do not affect wafer-printing results at all. The concept "Inspect all Repair only what prints" is introduced. In this paper a study comparing different defect classification methods and their impact on mask repair cycle time is presented.