Page 21 - Chip Scale Review_September-October_2023-digital

manufacture. Advanced packages such as manufacturers (OEMs) and Tier 1s may no served to remind us that semiconductor
flip-chip BGA (fcBGA), flip-chip chip- longer have this luxury for cutting-edge content requirements will only continue to
scale package (fcCSP) and low-density features. Vehicles are getting increasingly grow in the automotive domain.
fan out (LDFO) or complementary metal- electrified, for one thing, as electric Meanwhile, the zero-defect directive
oxide semiconductor (CMOS) image vehicle (EV) adoption and regulation gain is getting harder and harder to achieve.
sensors (CIS) are increasingly used steam. Vehicle componentry is getting The demand for automotive innovation is
in advanced driver assistance system dramatically more sophisticated in the pushing for the adoption of more leading-
(ADAS) applications. Diverse package evolution to levels 4 (high automation) edge chip technology into vehicles and
designs are being adapted to automotive and 5 (full automation) autonomous therefore is shrinking the “comfort zone”
functions to promote efficient and capable driving (Figure 3). Furthermore, recent time lag separating adoption cycles for
in-vehicle component configurations automotive semiconductor shortages have leading-edge consumer and automotive
despite significant space, power and
thermal constraints.

Lessons learned in mobile and HPC
apps
Inspection and metrology technologies
evolved in lock step with mobile device
technology (smartphones, tablets, etc.)
to accommodate advanced integrations
and varied chip form factors optimized
to fit within compact device enclosures.
Separately, H PC tech nolog y has
established multi-die package designs for
optimized thermal management leveraging
advanced heat sink techniques, which is
invaluable knowledge for vehicles designed
for harsh operating environments.
Together, mobile and HPC innovation We Take Care of the
have demonstrated the communication
improvements achievable between chips— Fine Work
the memory and processor, for example—
by moving the chip die physically closer
together. By stacking the chips on top of Wafer Level Packaging
each other (3D), or by placing them on an
interposer side-by-side (2.5D), or facing
each other on both sides of the substrate
(SiP), packaged devices can be more
compact while also achieving improved
communication bandwidth, which is critical.
Over time, the semiconductor content
has adapted to the environmental
conditions and available real estate; this
has paid-off through improved design REDISTRIBUTION LAYER COPPER PILLAR COMPONENT ASSEMBLY WAFER METALLIZATION
COMPONENT ASSEMBLY
flexibility that is now directly relevant and
applicable to the automotive domain. But
automotive applications also invite new
and similarly daunting challenges.
Automotive challenges
The automotive industry is, for good
reason, extremely conservative in its
approach to developing vehicle platforms. ELECTROLESS PLATING SOLDER BUMPING WAFER THINNING WAFER DICING
Risk is to be avoided at all costs, and
chip reliability is naturally paramount
to automotive safety. As a consequence,
automotive system designers prefer
tried-and-true technologies that are
validated and field-proven over decades.
However, automotive original equipment pactech.com

19
Chip Scale Review September • October • 2023 [ChipScaleReview.com] 19