X-RAY MASKS

An x-ray mask fabrication process producing virtually defect-free high -accuracy x-ray masks have been developd. Newly developed multi-exposu re electron-beam(e-beam) writing, (Cl-2 + O-2 + Ar)-ECR dry etching fo r Tapatterning, and one-point mounting methods are key techniques to a ttain high accuracy. The mask defect density is drastically decreased by introducing the polishing technique of the deposited SiN films. Die -to-die comparison of printed resist patterns using an e-beam x-ray ma sk inspection system is successfully applied to inspect x-ray masks. A focused ion beam x-ray mask repair system is used to repair mask defe cts. This mask fabrication process has led to the production of high-q uality x-ray masks with a reasonable yield.