Virtual metrology may never be 100% perfect because of the almost unlimited number of changes in a fab tools and the unique chip and wafer designs they're being used to process. But there are places where virtual metrology does make sense. Jon Herlocker, CEO of Tignis (now part of Cohu), talks with Semiconductor Engineering about why virtual metrology will never completely replace metrology tools in semiconductor fabs, where it has been used successfully, and what's included and not included in data collected by sensors on those tools. This is the fourth video in a seven-part series on AI in semiconductor manufacturing.
