The Wafer Metrology Centre Penta- Euripides project provided an open and highly modular hardware metrology platform – discover the Project Impact Summary

25 Mar 2024

Current metrology tools are often too monolithic and can’t be reconfigured to various and fast-changing needs. The Wafer Metrology Centre Penta – Euripides² project aimed to bring much more flexibility by creating a multi-sensor, highly and in-field adaptable hardware platform including also new sensor ideas. Providing the space and the appropriate environment for the different sensors while keeping tools and software compact was a challenge.

Project achievements and results

Within the Wafer Metrology Centre project, the consortium developed a unique modular hardware platform configurable for various applications. It can measure wafers both from top and bottom side and may use up to 10 parallel-mounted sensors of a variety of optical metrology technologies. All of them are made to be easy in-field exchangeable. Data streams from all the sensors may be combined and evaluated within the tool software to give more comprehensive insights. In the automation section we developed the industry first robot, which is capable to flip wafers with both hands, giving a throughput advantage and makes recipes easier. Furthermore, it can automatically exchange the handling hands to adapt to different wafers and frames. The same flexibility could be achieved with the new designed pre-aligner, able to manage very different wafer edge features.

The project also developed specific measurement sensors. In particular, it significantly enhanced the stability and homogeneity of digital holography over a large field of view, to allow single shot profiling of areas as large as a full lithography-shot with nm height resolution. In the mid-infrared range  demonstrator measures the spectra of light reflection about 100 times faster than currently available systems. Also, with our approach this speed doesn’t shrink with spectral resolution like in other common techniques. This will greatly enhance abilities for film thickness & structural metrology for new emerging materials. A proof of principle demonstrator could be created for a very high-speed 3D-profiler using several wavelengths and deploying an interference technique. It is intended to map contact structures (bumps and pillars) in the range of few microns size over the full wafer surface within less than 2 minutes. Complex correction mathematics had to be implemented to get rid of all the optical issues connected to these small, often mirror ball like features. Overall, a great step could be done to enhance wafer metrology in the direction of modularity and easy task adaptation.

Societal and Economic Impact

With the WMC project, the consortium tremendously increased the flexible adaptability and re-useability of the platform base, as a direct contribution to environmental footprint reduction by avoiding new platform manufacturing for every new task. This is an important step for the transition from existing more monolithic metrology products to the new platform idea. The WMC project could help European companies to get leadership in that market. Finally, the consortium initiated the creation of an ecosystem of European high-tech companies and Research Centres which will continue to co-operate beyond the project.

Future Developments

The consortium will continue the integration of multiple new sensors into the WMC. For the mid-IR laser sources, they started an assembly automation project including also a more advanced digital electronic. The holographic profiling will become fully integrated into the WMC and add single-shot, single nm height resolution 3D-profiles ability. The volume diffraction grid development as the essential part for the wide field-of-view sensor configuration is continued. The interference based high-speed 3D-profiler will go into the prototype phase, where they plan to achieve their speed and resolution targets.

Discover more about this project developments in the Impact Summary here.

Penta and Euripides² are Eureka Network Clusters operated by AENEAS.