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Figure 3: There are five levels of autonomous driving from: 1) driver assistance, 2) partial automation, 3) conditional automation, 4) high automation, and finally, to 5)
full automation.
devices (Figure 4). There’s a growing for optimal yield with no escapes of feasible, in many cases, to discard an
imperative [1] to achieve reliability faster faulty packages into the supply chain. entire multi-die package due to one
on newer technologies, from front end to Reaching the highest yield is particularly defective chip. In these loss scenarios,
packaging. As a consequence, high-end crucial for the economics of the industry. not only do chipmakers sacrifice the
defect screening is being increasingly Indeed, as 3D chip integrations grow value of the completed device, they
adopted by automotive fabs to reduce more complex and expensive—a single also squander all of the manufacturing
escapes for reliability-sensitive devices. multi-die package can cost thousands time and the power and resources it
Chip reliability is inextricably linked of U.S. dollars—it’s simply no longer required, multiplied for each and every
to yield because the defects that affect
reliability can be very similar to the ones
that affect yield, occurring perhaps in a
different location or at a slightly smaller
size. Actions taken during manufacturing
to reduce defectivity and improve yield
also have a positive impact on reliability.
To ensure high reliability on complete
multi-die assemblies, the quality must be
assured for each individual chip within
the package. A defect in any one chip
in the stack can have real-world safety
implications for vehicle occupants and
pedestrians. Furthermore, as packaged
multi-die chips proliferate throughout
vehicles, the failure risk is compounded.
Though the stakes are much higher
in automotive applications, there’s
an opportunity to apply the multi-die
integration lessons learned in mobile and
HPC applications to optimize packaged Figure 4: Traditionally, there has been a delay between the development of leading-edge Moore’s Law
component inspection and metrology semiconductor technology and the implementation into automotive applications for the increased reliability that
comes with process maturity. SOURCE: Oliver Senftleben, BMW

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