The Age of Virtual Metrology Begins
#Metrology is the technology of measuring key variables of products in manufacturing processes. For example, in #semiconductor #manufacturing, thickness, alignment, and feature sizes (called critical dimensions) are measured for a small fraction of wafers being processed in hundreds of steps. Too few measurements result in loss of in-line control and off-line traceability, whereas?too many measurements requires more money, time, and space.?The sampling rate, thus, becomes a fundamental tradeoff, subject to physical and financial constraints in high-volume manufacturing (HVM), especially for advanced manufacturing processes.
#VirtualMetrology (VM) is a solution to the sampling rate challenge of “physical” metrology. According to the SEMI E133 standard and the IEEE IRDS (International Roadmap for Devices and Systems), VM is the technology of prediction of post-process metrology variables using process and wafer state information that could include upstream metrology and/or sensor data. In a nutshell, VM provides all-wafer measurements without adding new hardware (other than data and computing infrastructures), breaking the fundamental tradeoff imposed on the overall metrology capacity.
Isn’t VM a wonderful idea — almost like a free lunch? The idea itself is not new and traces back to a conference paper in 2005, followed by more than 300 papers and patents from academia, chip makers, equipment vendors, and fab software suppliers. So is VM used broadly in HVM fabs by now? Well, some say, “we are still working on it — as we have been for the last 15 years”. Many more say, “we gave up on it.” Simply put, the problem is too difficult. You can read more about the practical challenges of VM from the following article from Semiconductor Engineering . So VM has been a pipe dream with no viable solution for real HVM fabs — until Panoptes VM made it a reality.
#PanoptesVM is a groundbreaking solution that opens new possibilities in HVM. First, Panoptes VM is highly accurate whenever, wherever — predicted values from Panoptes VM closely track real measurement values robustly against drifts and shifts, and universally across various devices, tools, recipes, and measurands. Second, Panoptes VM is built for engineers by engineers — the setup requires only minimal inputs from process engineers, and subsequent operations, such as model update and maintenance, are completely automatic. Third, Panoptes VM is operable at the fab scale — it is deployed alongside on-prem fab software systems, handling 10,000s of models reliably.
These features — #accuracy, #usability, and #scalability — augment one another simultaneously, which makes Panoptes VM truly unparalleled. In a sense, these features reflect the unique combination of talents at Gauss Labs — AI algorithm expertise, manufacturing domain knowledge, and SW architecting capabilities.
领英推荐
I will delve into more detail in the next couple of newsletters, but you are welcome to reach out to me for more information. In fact, we will present a talk on VM at the Smart Manufacturing Forum at #SEMICON_WEST 2023 and exhibit Panoptes VM and other products in Booth #1765. As a reader of this newsletter (and hopefully a subscriber), you are cordially invited to the event. Please click the following link for a complimentary expo pass. Look forward to seeing you in San Francisco!
Regards,