Abstract: The use of programmed defect test reticles to characterize automatic defect inspection equipment has long been an established practice in the maskmaking industry. Measurement of the defect sizes on these programmed defect test masks is not necessary if one only desires to qualitatively investigate differences in system performance. However, more meaningful comparisons in inspection system performance require a calibrated programmed defect test mask. Historically, commercially available programmed defect test reticles have not had traceable or well-documented defect sizing methods nor was information regarding the precision of these measurements provided. This paper describes the methods used and results obtained from the work performed to address these issues. Using a low voltage scanning electron microscope as an image acquisition system, defect sizing is accomplished using automated pattern recognition software. The software reports defect size metrics such as maximum inscribed circle diameter and area. Measurement precision better than 30 nm has been demonstrated for the maximum inscribed circle method. The correlation of SEM based measurements to historical optical metrology measurements ia also discussed.!1
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