Advanced Optical Metrology Solutions for AI Packaging Processes

3:50 pm - 4:20 pm

High-performance advanced packaging—centered on 2.5D/3D integration has become a key driver in AI chips' evolution. While these architectures boost performance, their increasing process complexity poses challenges for high-yield manufacturing and long-term reliability. Among them are vertical scaling challenges, such as those related to TSV’s, and demanding wafer-level geometry and topography requirements. Metrology must therefore evolve to deliver innovative, versatile solutions that preserve an acceptable Cost of Ownership for semiconductor manufacturers. In our proposed talk, we’ll demonstrate how interferometry is utilized to address this challenge, covering a broad range of advanced packaging applications.

Wafer-level metrology for post-stacking and bonding in 2.5D integration and HBM
These processes pose serious challenges. For instance, side-by-side packaging of materials with different thermal expansion coefficients can result in several millimeters of wafer warpage, while non-uniform die shapes and densities create asymmetric geometries. These deformations can escalate into yield-killing failures such as stress-driven cracks or voids. Spectral Coherence Interferometry enables rapid, direct metrology for wafer and die-level warpage with high accuracy, essential for identifying process deviations. This technology also provides thickness and Total Thickness Variation (TTV) measurements for complete stacks and individual layers. This is especially critical in HBM manufacturing, where tight stacking tolerances require that each die meet precise thickness specifications to ensure alignment and bonding integrity.

Interconnects and post-CMP metrology in 3DIC
As the industry moves into the next phase of advanced packaging, interconnects are being implemented at the silicon level, often on complex multilayered stacks. We will showcase innovative solutions, combining Spectral Interferometry with OCD modeling capabilities, tailored for the most demanding 3DIC and hybrid bonding applications, and deliver accurate, robust results through direct measurements. These solutions offer proven advantages in the inline characterization of critical process elements, including TSVs, Cu pads, RDLs, and pre-bonding wafer-edge topography.

Featured Speakers

Fabian Schneider

Applications Group Manager, Nova

Dr. Fabian Schneider is a semiconductor metrology professional with over six years of experience in semiconductor metrology and 15 years in optical systems.

Mr. Schneider joined Nova Ltd. as part of the acquisition of Sentronics Metrology, which was completed in February 2025. In his current role, he manages the applications group of Nova's Sentronics line of products, responsible for addressing customers’ metrology needs and maximizing the value they gain from these advanced products. Prior to that, Mr. Schneider was a scientist in a group working on high-precision laser spectroscopy of short-lived heavy atoms.

Dr. Fabian Schneider holds a M.Sc. in physics from TU Darmstadt, Germany, and continued his physics studies with a PhD at the University of Mainz, Germany.