Scatterometry measurement for gate ADI and AEI CD of 28nm metal gates

摘要

For reduced gate leakage and enhanced device performance, many IC manufacturers utilize novel metal gate technologies instead of traditional poly silicon gates. The new materials and geometries required to form metal gates mean that new parameters control the optimization of device performance [1]. Traditional gate process control has relied heavily on scatterometry for ensuring that variation in structural dimensions remain in control, as some dimensional deviations can strongly affect device performance. A new-generation scatterometry tool with multiple extensions to traditional scatterometry technology is evaluated as a production process monitor for complex metal gate structures at the 28nm device node and beyond.