July 10, 2011 — While following the semiconductor industry’s technology roadmap, manufacturers have again realized a need to increase wafer size. Economic modeling indicates significant economy-of-scale benefits in moving to 450mm wafers. However, the shift also presents the industry with a new set of logistical and infrastructure challenges.
For guidance, manufacturers and suppliers can reflect on the last time the industry moved to an increased wafer — 200 to 300mm wafers — and anticipate some challenges in wafer transport and protection in the fab environment.
Wafer fragility. Increased wafer size means increased fragility. This is because the larger wafer is proportionally thinner and has a lower natural frequency than the 300mm wafer. Therefore, its response to vibrations observed under normal shipping methods will be more severe. Careful handling with a robust secondary packaging system is crucial to help avoid breakage.
Wafer sag. The proportionally thinner wafer also increases the potential for a 450mm wafer to sag or