Using scatterometry based on Spectroscopic Ellipsometry, a complete study of Gate lithography level measurement on standard products has been conducted. Experiments were done on typical ST batches for 120, 90, and 65 nm (EbeamDirectWrite) nodes. KLA-Tencor SpectraCD SE system is used to collect and analyse line critical dimensions and profiles. A systematic correlation with Scanning Electron Microscope (SEM) is done, completed by a cross section analysis. The study also takes into account lithography defect analysis using specific targets with intentionally generated process failures. Our objective is to determine the sensitivity window of such measurement technique to process defect and marginal process conditions. We show that KLA-Tencor SpectraCD allows, a full reconstruction of the line profile - as well as the film stack underneath it - with values that are in agreement with production control. Cpm values (>15) obtained on products demonstrate that SE based scatterometry fulfils all requirements to be integrated in a production environment and provides suitable metrology for advanced lithography process monitoring.
