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then check overall position and tilt, while
looking for any issues like cracks induced
by the assembly process.
As an industry, we’ve largely held a
siloed view of front-end semiconductor
processes, IC substrates and packaging.
But as these technologies continue to
evolve and overlap, we envision that shared
learning will make it possible to implement
new process control strategies for
Figure 7: Advanced 3D metrology imaging techniques. Project fringes of light at multiple angles on the
package (left), and capture with a camera. Changes in height (z) create a phase shift in the resulting image semiconductor content at multiple stages
(center). Height information can be revealed in Z-maps by combining multiple images with algorithms (right). of the integration process, in automotive
applications and elsewhere.
ball bed: their relative heights must • Maximized tool functionality for
be reconciled to ensure that a tilt or high-volume manufacturing; and Summary
mispositioning of the capacitor isn’t • High-speed production with high Inspection and metrology techniques
causing it to prevent optimal contact yield. for advanced packages in the automotive
of solder balls with the printed circuit domain are squarely aimed at optimizing
board (PCB) (Figure 6). In order to do At the end of the assembly line, an yield and preventing defective chips from
these types of measurements, advanced advanced inspection and metrology being missed, in part by enabling accurate
imaging techniques are used to ensure strategy provides packaging manufacturers classifications so that escapes don’t result
high accuracy and repeatability. In with the data required to improve their in safety issues down the road. Mobile
Figure 7 we see how projection of yield while effectively sorting components and HPC applications taught us a lot in
light fringes and analysis of their phase so that defective parts are quickly this regard, and stringent automotive
shift can provide Z-maps of device removed (and potentially restored). In the applications will teach us even more.
surfaces, and then to the determination future, similar high-end process control Advancements in optics provide flexible
of critical dimensions. Advanced approaches could be applied earlier in the illumination with high-resolution during six-
metrology techniques like this can be process, i.e., during assembly, to detect sided inspection for finding and classifying
designed to achieve enhanced accuracy critical issues sooner. smaller defects. This is complemented with
and repeatability, together with large When integrating multiple, expensive die faster, flexible metrology with high accuracy
FOV required for fast processing. in an advanced 3D package, it’s naturally and repeatability.
beneficial to detect defects as soon as All of the above combined with deep
Benefits today and tomorrow they arise, well before final assembly. In- learning’s crucial role in automating
Advanced defect inspection supported process inspection will also give a better process uniformity and accurate binning
by innovative deep learning solutions along insight into the package. When performed are coming together to provide packaging
with high accuracy, high repeatability only at the end of the assembly process, manufacturers with what they need to
metrology techniques help to enable 360-degree inspection merely extends to improve yield and reliability. We anticipate
component-level reliability and quality the outer layer of the assembled package— that future innovation in “interim
control for safety-critical automotive after all inspection visibility into the inspections” occurring during multi-die
applications. These innovations will help assembled package is lost. assembly could further pave the way for
to support the following: In the future, advanced inspection and yield improvements and cost optimizations
metrology may not only be, as it is today, across the automotive domain.
• Wider range of devices (smaller, for the incoming integrated circuit (IC)
bigger, thinner, 3D, irregular); substrate and the final packaged chip, but Reference
• More complex features with smaller could be expanded to include testing of the 1. https://www.reuters.com/business/
defects; “building blocks” of the multi-die devices, autos-transportation/tsmc-aims-get-
• Stricter tolerances for modular i.e., at pre-assembly. Manufacturers would newest-chip-technology-into-cars-
assembly; embrace an interim opportunity to, for faster-2023-04-26/
• Higher quality requirements; example, add a die on the IC substrate and

Biography
Olivier Dupont is Product Marketing Director at KLA Corporation, Leuven, Belgium. With a PhD in
engineering, Olivier Dupont began his career in R&D, then shifted to more customer-facing roles. With this
move, he developed an understanding of market needs and experience in product management. After working
in various industries, Olivier joined KLA in 2018. As product marketing director, he leads the ICOS Component
Inspection Tool portfolio and roadmap. Email olivier.dupont@kla.com

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