Cognex offers vision-based wafer pre-alignment

The Cognex In-Sight® 1820 vision-based wafer pre-aligner uses the company’s proprietary NotchMax technology. The 1820 vision system determines wafer position and orientation in less than half a second while mechanical pre-aligners typically spin wafers for several seconds. NotchMax, the newest member of Cognex industry-leading PatMax family of geometric pattern finding technologies, aligns wafers with a centre position accuracy of ±15 micron and an orientation accuracy of ±0.05 deg. More accurate pre-alignment saves fine alignment steps inside a process tool to boost throughput. Cognex says that in addition to throughput and accuracy gains, capital equipment manufacturers will appreciate the system’s ability to handle changing wafer sizes and types with simple parameter changes, while semiconductor fabs will like the non-contact design that minimises wafer handling and potential damage to the wafer.