Global and semi-global communication on Si-IF

Abstract

On-chip scaling continues to pose significant technological and design challenges. Nonetheless, the key obstacle in on-chip scaling is the high fabrication cost of the state-of-the-art technology nodes. An opportunity exists however, to continue scaling at the system level. Silicon interconnect fabric (Si-IF) is a platform that aims to replace both the package and printed circuit board to enable heterogeneous integration and high inter-chip performance. Bare dies are attached directly to the Si-IF at fine vertical interconnect pitch (2 to 10 μm) and small inter-die spacing (≤ 100 μm). The Si-IF is a single-hierarchy integration construct that supports dies of any process, technology, and dimensions. In addition to development of the fabrication and integration processes, system-level challenges need to be addressed to enable integration of heterogeneous systems on the Si-IF. Communication is a fundamental challenge on large Si-IF platforms (up to 300 mm diameter wafers). Different technological and design approaches for global and semi-global communication are discussed in this paper. The area overhead associated with global communication on the Si-IF is determined.