Chiplet and CoWoS: Post-Moore Packaging Guide

Introduction#

For decades, the semiconductor industry relied on transistor scaling to deliver exponential performance growth. As Moore's Law slows and physical limits approach, the cost of shrinking transistors becomes prohibitive. Advanced packaging has emerged as the new frontier for continuing performance gains, with Chiplet and CoWoS leading the way.

This article analyzes how heterogeneous integration, often described as a building-block approach, allows designers to break through the limitations of monolithic chips. By combining multiple smaller dies into a single package, chiplet-based design offers a practical path to improve functionality, yield, and cost efficiency in the post-Moore era.

Understanding Chiplet and CoWoS#

A chiplet is a functional block or die that performs a specific role, such as computation, memory, or I/O. Instead of fabricating one massive system-on-chip, designers partition the system into smaller dies, then integrate them side by side on an interposer using 2.5D packaging or stack them vertically in 3D packaging.

CoWoS, which stands for Chip-on-Wafer-on-Substrate, is a 2.5D integration technology that places multiple chiplets on