What is a Multi-Die Chip?

Key Takeaways

• Multi-die chip designs partition large designs into smaller dies, improving yield and achieving power and form factor goals.

• Different packaging technologies, including 2.5D and 3D, offer options for integrating chips and optimizing performance.

• Industries like high-performance computing, mobile, automotive, and silicon photonics are adopting multi-die chip designs to enhance their products and meet evolving market demands.

Silicon dies located on a wafer

In the ever-evolving landscape of chip manufacturing, traditional approaches to achieving power/performance goals, functionality, form factor, and cost have relied on the transition to smaller process nodes. However, the demand for processing power has pushed monolithic System-on-Chip (SoC) designs to sizes that are challenging to fabricate with acceptable yields. Additionally, the diminishing returns of advanced nodes have made it economically impractical to accommodate all of the required logic, IO, and memory for compute-intensive applications within the limits of manufacturing equipment.

Multi-Die Chips

To overcome process node limitations, chip designers have embraced a paradigm known as multi-die design, where large designs are partitioned into multiple smaller dies, often referred to as chiplets or tiles. These chiplets are then integrated into a single package. In combining these chiplets, desired power and form factor goals can be achieved. 

Unlike monolithic designs that incorporate all functionality on a single piece of silicon, multi-die approaches offer both modularity and design flexibility, enabling the mixing and matching of separate dies to cater to different market segments or specific needs.

Multi-Die Chip Advantages

This flexibility extends to the ability to utilize different process nodes for a multi-die design, allowing for the optimization of technology nodes for specific requirements, overall system performance, and cost targets. Rather than attempting to move down another node, design teams may find that utilizing a multi-die system may be more cost-effective. 

With the potential to house trillions of transistors, multi-die systems empower designers to allocate dies to particular functions and process technologies, easing fabrication processes and producing better yields. 

Multi-Die Chip Integration

When an SoC is partitioned into separate modules, designers must adopt a system-wide approach, considering both performance and cost implications. Due to the added complexity of multi-die designs, it becomes crucial to co-design them with a comprehensive understanding of factors such as thermal footprint, signal and power integrity, mechanical considerations, routing complexities, and other essential parameters.

The architecture of a multi-die design offers various formats to accommodate different needs. One prevalent and cost-effective approach involves placing dies side-by-side and connecting them through dedicated die-to-die interfaces. 

Multi-Die Chip Use in 2.5 and 3D Packages

For higher density, a 2.5D or 3D package can be assembled, enabling greater integration of blocks. High-speed SerDes architectures are well-suited for 2D and 2.1D packaging, as they align with their characteristics. On the other hand, high-bandwidth parallel architectures can take advantage of the enhanced routing density provided by 2.5D and 3D packaging, enabling efficient data transfer between dies.

For systems that require multiple instances of the same or similar ICs, such as memories, chip-stacking is a viable option. By skillfully designing the substrate, these dies can be vertically stacked, significantly reducing the footprint of the resulting Multi-Chip Module (MCM). This approach does come with the trade-off of a thicker or taller chip. Nonetheless, in compact electronic designs where space is at a premium, the chip-stack presents an appealing option. 

The connections between the dies play a critical role and must be power-efficient, have low latency, and be capable of providing high bandwidth to facilitate the transfer of massive amounts of data between the dies, all while ensuring error-free operation. System analysis, whether in 2D or advanced 2.5D or 3D configurations, needs to consider the coupling effects of through-silicon vias (TSVs), through-dielectric vias (TDVs), redistribution layers (RDLs), interposers, and substrates.

Multi-Die Chip Design Adopters

The adoption of multi-die chip design is gaining momentum across various industries as industry leaders seek to capitalize on the benefits offered by this architecture. In high-performance computing (HPC) and hyperscale data center spaces where compute-intensive workloads are prevalent, multi-die designs are being embraced to meet the demands of these environments. 

Multi-Die Chips in Industry

Mobile chip designers are also exploring the potential of multi-die architectures, taking advantage of the power, performance, and area (PPA) benefits of their space-constrained devices. Automotive chip designers have also recognized the advantages of multi-die architectures, exemplified by the adoption of such designs by companies like Tesla.

Multi-Die Chips in New Technologies

Another area of significant development is silicon photonics, a technology that utilizes light for data transmission and processing. Silicon photonics is being integrated into heterogeneous multi-die packages, providing energy-efficient bandwidth scaling. 

As these sectors continue to evolve, they will closely monitor and leverage the progress in multi-die chip design to enhance their products and meet the evolving demands of their respective markets. Whether driven by cost-effectiveness, PPA advantages, or accelerated time-to-market, the widespread adoption of multi-die systems is poised to revolutionize the semiconductor industry, unlocking higher levels of performance and transforming the applications that shape our lives.

Allegro X Advanced Package Designer is a powerful tool that encompasses all aspects of the packaging process. With the increasing adoption of multi-die chip designs, Allegro X Advanced Package Designer is the industry's leading solution for designing and integrating chiplets or tiles into a single package. Its advanced features and comprehensive capabilities empower designers to co-design multi-die systems, considering factors such as thermal footprint, signal integrity, power integrity, routing complexities, and more to ensure optimal performance and cost efficiency.

Leading electronics providers rely on Cadence products to optimize power, space, and energy needs for a wide variety of market applications. To learn more about our innovative solutions, talk to our team of experts.