YAP+: Pad-Layout-Aware Yield Modeling and Simulation for Hybrid Bonding

TL;DR

YAP+ is a comprehensive, fast, open-source yield modeling framework for hybrid bonding in 3D integration, accounting for layout-aware failure mechanisms and enabling optimized design strategies.

Contribution

It introduces a novel, near-analytical yield model for hybrid bonding that incorporates layout-aware failure analysis and demonstrates significant speed improvements.

Findings

Model accurately predicts yield with over 1,000x speedup.

Pad layout patterns significantly impact bonding yield.

Redundant pad placement can improve overall yield.

Abstract

Three-dimensional (3D) integration continues to advance Moore's Law by facilitating dense interconnects and enabling multi-tier system architectures. Among the various integration approaches, Cu-Cu hybrid bonding has emerged as a leading solution for achieving high interconnect density in chiplet integration. In this work, we present YAP+, a yield modeling framework specifically tailored for wafer-to-wafer (W2W) and die-to-wafer (D2W) hybrid bonding processes. YAP+ incorporates a comprehensive set of yield-impacting failure mechanisms, including overlay misalignment, particle defects, Cu recess variations, surface roughness, and Cu pad density. Furthermore, YAP+ supports pad layout-aware yield analysis, considering critical, redundant, and dummy pads across arbitrary 2D physical layout patterns. To support practical evaluation, we developed an open-source yield simulator, demonstrating that our near-analytical model matches simulation accuracy while achieving over 1,000x speedup in runtime. This performance makes YAP+ a valuable tool for co-optimizing packaging technologies, assembly design rules, and system-level design strategies. Beyond W2W-D2W comparisons, we leverage YAP+ to investigate the impact of pad layout patterns, bonding pitch, and pad ratios across different pad types, and explore the benefits of strategically placing redundant pad replicas.