Automatic CD-SEM offline recipe creation in a high volume production fab

Abstract

CAD based recipe creation paves the way for complete recipe automation and minimizes the need for human intervention. A high volume production environment presents its own unique challenges for automatic CAD based metrology. In our work we describe the approach of automatic offline CD-SEM recipe creation for production using the Applied Materials OPC Check application. In addition, the study includes a comprehensive analysis of success rates for recipe creation, pattern recognition and measurement. The stability of automatically created recipes was evaluated against process variations for a number of test structures which are typically used for production control. Data was collected for various layers on multiple lots and the performance was compared to that of recipes created directly on the tool.All offline recipes for production were generated waferless from design data with success rates of 100%. They showed pattern recognition success rates and measurement success rates at the same level or better than the rates typically reached by recipes created directly on the tool by an experienced CD-SEM engineer.