The semiconductor industry is facing critical challenges in scaling performance, energy efficiency, and integration density. As traditional 2D scaling approaches reach their physical and economic limits, 3D integration—including die-to-wafer (D2W) hybrid bonding and through-silicon vias (TSVs)—has emerged as a key technological pathway for future chips architectures. The demand for compact, high-bandwidth, and heterogeneous system integration is growing, particularly for edge AI, HPC, and next-generation communication systems.

In this context, the European Union’s PREVAIL project is built around three key technological pillars to strengthen Europe’s sovereignty in edge AI hardware. These pillars are: Embedded Non-Volatile Memories (eNVM), 3D Integration Technologies, Photonics and RF connectivity. Coordinated by CEA-Leti, PREVAIL focuses on establishing a 300 mm pilot line capable of supporting the development and validation of chiplet-based architectures. The pilot line integrates high precision die-to-wafer and wafer-to-wafer solutions, TSV etching and deposition capabilities, as well as characterization tools to serve the growing needs of both industry and research.

By mid-2025, several essential process tools have been delivered, installed, and partially qualified. Notably, a high precision pick and place bonding system and tools dedicated to PVD metal and PECVD dielectrics depositions for 3D integration will be operational for Q3 2025. Half of the pieces of equipment planned in the investment roadmap are now ready for process start, and the rest will be by the end of the year, supporting the build up of process flows for two major demonstration modules: a small pitch (3µm) hybrid bonding flow (D2W) and a TSV-last interconnect flow. These modules enable the fabrication and electrical tests of stacked dies using newly developed process modules. Test vehicles such as the BALI mask set (see previous FAMES news), and their associated PDKs, are used to validate each integration step.

The FAMES project provided the strategic alignment, R&D framework and consistent applications for bringing PREVAIL tools to the next level. Through FAMES, key process developments complementary to those initiated in PREVAIL—such as very small pitch hybrid bonding assemblies, TSV metallization filling, and die-level thinning—have been accelerated and supported at CEA-Leti, in collaboration with other RTOs.

These results mark a crucial milestone for the FAMES project by establishing the infrastructure required to demonstrate scalable, high-density 3D integration flows. The validation of hybrid bonding D2W assemblies and TSV modules on a 300 mm line provides a foundational capability for future 3D chiplet architectures, supporting both prototyping and small-volume production scenarios in the long run.

Looking ahead, the PREVAIL line will be used to support developments in AI accelerators, heterogeneous computing platforms, and advanced 3D system-in-package (SiP) designs. The qualified equipment and process modules will boost technology transfers to European industry and as a reference for future collaborative projects.