Preface
There is a lot of buzz in the industry about More-than-Moore technology directions,
and especially the 2.5D and 3D System in Package (SiP) integration options. In
principle, More-than-Moore integration, and 2.5D and 3D SiP implem entation, is
an opportunity that can be leveraged to extend system level miniaturization without
More-Moore type of scaling, and to bring incremental cost-power-performance
value. At a superficial level, it would appear that the SiP concept of integrating
multiple die in a package—either by putting them side by side (2.5D inte gration) or
on top of each other (3D integration)—is pretty straightforward, and not all that
novel. This would seem especially so now that the key enabling foundational
technology modules, such as the Through Si Vias and the uBumps, have been
proven out, and are in volume manufacturing. After all, there are several announced
SiP products that leverage the 2.5D a nd 3D integration technologies, and more are
rumored to be coming. So, what is the big deal?
However, in practice, implementation of competitive 2.5D and 3D SiPs for
mainstream products—especially for cost conscious consumer market—is chal-
lenging. The entire IC product design and sourcing ecosystem, and the standard
industry practices and methodologies, have all been optimized over the last few
decades for sourcing 2D SoC type of products, and are therefore challenged by
some of the requirements for, and uniqueness of, 2.5D and 3D SiPs. Thus, adoption
of 2.5D and 3D technologies is disruptive to the standard industry paradigms.
The intent of this book is to explore the tradeoffs that need to b e considered in
order to make 2.5D and/or 3D integration technologies attracti ve for use in high
volume IC components targeting consumer products, competing in, for example,
the mobile mark et. The new degrees of freedo m offered, as well as the new con-
straints imposed by these integration technologies are in fact quite insidious. The
tradeoffs required to optimize a 2.5D or 3D SiP products and make them com-
petitive versus traditional 2D SoC IC are complex, mutually interdependent,
involve architecture, design, Si and package technologies, have consequences in
multiple physical domains, and impact both the technical and business considera-
tions. It IS complicated!
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