3D integrated circuits: designing in a new dimension

Moore's law predicted the sustained scaling the semiconductor industry has enjoyed for decades, but in the coming decade the limits of physics will force the pace of geometric scaling to slow and perhaps all but stop. In the face of this issue, the electronics industry needs alternatives that can give end consumers the continual increase in function and reduction in cost that they have come to expect. 3D integrated circuits have emerged as the near term solution to mitigate the roll-off of geometric semiconductor scaling.

The power of 3D circuit integration comes from its ability to reduce wire length. The ramifications of this are more numerous and powerful than one might initially realize. The shortened wires improve speed and reduce power, but they also allow new combinations of technologies optimized for the performance of specific circuitry. 3D wiring changes alone might provide a 5--30% device improvement, but combining disparate circuit types and using 3D optimized architectures could enable 100--500% improvements.

This paper discusses the benefits of 3D and the methods of producing various types of 3D and examines various examples ranging from imagers to exascale computing memories. It also presents an overview of the new requirements that 3D EDA tools must address to effectively handle 3D integration and describes some of the tools that are already available.