Automatic Mask Pattern Localization

In collaboration with KLA-Tencor, XYALIS will present an article during the poster session of the SPIE Advanced Lithography conference in San Jose, California, USA, 21-25 february 2016.

Automatic pattern localization across layout database 
and photolithography mask


Advanced process photolithography masks require more and more controls for registration versus design and critical dimension uniformity (CDU). The distribution of the measurement points should be distributed all over the whole mask and may be denser in areas critical to wafer overlay requirements. This means that some, if not many, of theses controls should be made inside the customer die and may use non-dedicated patterns. It is then mandatory to access the original layout database to select patterns for the metrology process.

Finding hundreds of relevant patterns in a database containing billions of polygons may be possible, but in addition, it is mandatory to create the complete metrology job fast and reliable. Combining, on one hand, a software expertise in mask databases processing and, on the other hand, advanced skills in control and registration equipment, we have developed a Mask Dataprep Station able to select an appropriate number of measurement targets and their positions in a huge database and automatically create measurement jobs on the corresponding area on the mask for the registration metrology system. In addition, the required design clips are generated from the database in order to perform the rendering procedure on the metrology system.

This new methodology has been validated on real production line for the most advanced process. This paper presents the main challenges that we have faced, as well as some results on the global performances.