As reticle line widths shrink and RET complexity increases, even a single sub-micron defect can reject a photomask.
High-end reticle manufacturers striving for increased yield and reduced cycle times are relying on low incoming
rawstock defect levels and handling via SMIF mini environments for critical manufacturing steps. However, even in
SMIF compatible reticle fabs, human handling is often required to load or unload a reticle to/from a SMIF environment.
In an effort to provide a fully integrated solution to manufacturing 65 nm and below photomasks, Photronics has
introduced a blank inspection/management system developed by Hitachi High Technologies and Fortrend Engineering.
The clustered system is capable of robotic transfers in conjunction with blank storage, inspection, and material tracking
capabilities. It consists of four major systems: a horizontal mask blank transfer system with state-of-the-art blank
sorting capability, an integrated Hitachi GM3000 Mask Blank Surface Inspection System, a totally self-contained and
sufficient Mask Blank Storage Station, and a material logistic control software system for material management and
SPC. The Fortrend Lamina sorting system has a bright light inspection module for gross particle contamination
detection, and a robotic transfer module for mask exchanges between SMIF and other shipping/transport boxes
employed in the mask manufacturing facilities.
The clustered Hitachi inspection system is an integral part of the solution allowing for additional inspections of stored
and incoming blanks by optically detecting foreign particles and pinholes. The data is transferred and stored in the
Foretrend handling system control module and may be used for rawstock management and screening based on a
predefined criteria. The integrated system provides a total solution to mask manufacturing challenges at 65 nm and