The exponential growth in test data volume for modern Systems-on-Chip (SoCs), combined with a decreasing number of available test pins, has led to increased test time and complexity. Simultaneously, the industry’s drive for higher quality and lower Defective Parts Per Million (DPPM) necessitates continuous monitoring, testing, and repair Silicon Lifecycle Management (SLM). The advent of multi-die packaging technologies, such as 2.5D and 3D stacked integration, further exacerbates these challenges by introducing additional layers of interconnect and access constraints.Universal Chiplet Interconnect Express (UCIe) emerges as a compelling solution for delivering test content to all constituent dies at-speed, post-packaging. UCIe enables seamless test access across various lifecycle stages, including wafer sort, package test, System Level Test (SLT), and In-System Test (IST).This paper introduces a silicon-proven methodology that integrates the UCIe protocol with advanced SLM techniques to address the critical challenges of access, test, measurement and repair in complex multi-die SoC designs. Silicon results from test vehicles fabricated on TSMC N3P process with CoWoS-S packaging demonstrate complete interconnect, logic, and memory test, repair, and monitoring capabilities, validating the effectiveness and scalability of the proposed approach for next- - generation multi-die systems.

A multi-die 3DIC is constructed by integrating multiple dies into a stack. These dies are interconnected via die-to-die (D2D) interconnects facilitated by I/O pads, which manage signal load and provide electrical protection to both the die and the overall system. The number of D2D interconnects is anticipated to increase significantly, rising from a few thousand today to several hundred thousand in the coming years. Consequently, ensuring the functionality and performance of 3DIC systems requires rigorous testing of not only the die logic but also the pads and interconnects at both the die and stack levels. In this paper, we explore the Design for Test (DFT) and testing challenges involved in handling various types of pads, ranging from simple to complex custom designs, within a multi-die 3DIC system. We also examine the tools and methodologies provided by Electronic Design Automation (EDA) tools to support these challenges, specifically focusing on implementations compliant with the IEEE 1838 standard.

Chip-Iet based multi-die 3DIC design methodology is the paradigm shift in semiconductor manufacturing that enables scalable design integration for SysMoore era. Stacking multiple heterogeneous dies in a single stack opens chip design to a world of unexplored challenges. One such challenge is testing of the individual dies and the integrated complex stack to improve DPM. The IEEE 1838 standard defines 3DIC DFT architectures for individual dies and stack level test. In this paper we present a case study on an industrial design to leverage EDA tools and flows to implement IEEE 1838 compliant DFT architectures for full die and integrated stack.

With the increasing demand for on-chip embedded memories in System-on-chip (SoC), the percentage of memory cells in the designs are going up. This raises two major requirements for the manufacturability of such SoCs, adequate testing of the memory cells to ensure acceptable DPPM levels and the need for test logic implementation to be optimized to meet physical implementation requirements in terms of routing, signal integrity, and power integrity. This paper proposes a method to allocate a physically aware Memory Built-in Self-Test (BIST) processor to memories under test using the Floorplan Design Exchange Format (DEF) at the register transfer level (RTL). The proposed method considers the physical location and connectivity of the memory instances in the chip design, enabling a more efficient allocation of the Memory BIST processor. Besides physical awareness for routing feasibility, clock domains, voltage islands, and switching activity aspects are also considered during Memory BIST processor assignment for a group of memories under test. The proposed method is demonstrated for various design scenarios. The results show that it achieves significant improvements in terms of timing closure, IR drop, test time, and area overhead compared to existing methods, and better alignment with the functional mode of operation.