Last month I wrote about how my colleagues and I believe that embedded processor vendors will need to become more involved in developing or acquiring proprietary algorithms to stay competitive in the coming decade. This month, I’ll discuss another long-term trend that we expect to see in processor-based chips: the dramatically expanded use of multi-die packaging (also called “system-in-package”).
We all know that integration of more functionality at the silicon die level has some powerful advantages relative to using separate components – such as reduced size, power consumption, and cost, along with (potentially) better reliability. But die-level integration also has some serious disadvantages. For one thing, it’s expensive to design, verify, and fab lots of different, complex dies with lots of different combinations of on-chip peripherals, memory sizes, co-processors, etc. But if you want to be able to effectively address a wide variety of applications, you need many chip variants. So processor vendors are forced to make difficult trade-offs in terms of how many chip variants they offer, and system designers usually don’t get the exact feature mix they want.
Then there are the fabrication challenges. It’s becoming increasingly common to incorporate multiple technologies on a single chip: logic, MEMS, analog, flash memory, RF, etc. But when such different technologies are on a single die, they aren’t all going to be fabricated in a way that’s optimal for each of them. Somebody’s (or maybe everybody’s) speed, power, or cost is going to have to be compromised.
With system-in-packaging, on the other hand, you can use whichever fab approach is best for each technology, and then bring them together onto one chip at the end. Chip vendors can verify each die design separately and then mix-and-match components to their heart’s content.
A few vendors are already taking advantage of the system-in-package approach for selected applications, but it’s still in its infancy. I believe it’s going to become a central aspect of the chip business in the coming years. If so, chip companies with expertise in (or access to) system-in-package technology, and to a broad spectrum of silicon technology (logic, memory, analog, RF, etc.) will be well positioned to pull ahead of their competitors. Doing so will require a significant shift in chip companies’ mindsets and expertise, along with substantial investments.
Jennifer Eyre White of BDTI contributed to this article.