Why Interposers Matter More Than You Think

When people talk about advanced semiconductor packaging, attention is usually focused on cutting-edge chips: smaller transistors, faster logic, or higher power devices. Yet between these chips sits a less visible but increasingly critical component—the interposer.

Traditionally, an interposer has been viewed as a passive structure, whose main task is to route signals between chips. However, as computing systems move toward chiplet architectures, higher power densities, and more demanding thermal environments, this passive role is no longer sufficient. The interposer is now expected to carry electrical signals, withstand mechanical stress, and manage heat—all at the same time.

This shift is precisely where 12-inch silicon carbide (SiC) interposers enter the picture.

From Silicon to Silicon Carbide: A Change in Philosophy

Most interposers today are made of silicon, largely because the semiconductor industry already has mature 12-inch silicon manufacturing infrastructure. Silicon interposers work well for high-density wiring, but they begin to show limitations when systems operate at high power or elevated temperatures.

Silicon carbide offers a fundamentally different set of material properties:

• Much higher thermal conductivity, enabling faster heat removal

• Superior mechanical stiffness, improving dimensional stability

• Excellent thermal and chemical stability, even at high temperatures

Because of these properties, SiC interposers are not just better versions of silicon interposers—they enable a different design philosophy. Instead of treating thermal management as an external problem solved by heat sinks or cold plates, SiC allows heat to be managed directly at the interposer level.

Why the 12-Inch Format Is a Big Deal

At first glance, moving from smaller wafers to 12-inch SiC interposers may appear to be a simple scaling exercise. In reality, it represents a major step toward industrialization.

The 12-inch format matters for several reasons:

• Manufacturing compatibility with advanced lithography, inspection, and packaging tools

• Higher throughput and lower cost per unit area at scale

• Support for large interposers, which are essential for multi-chip and heterogeneous integration

However, scaling SiC to 12 inches is far more challenging than scaling silicon. Defect control, wafer flatness, and stress management all become significantly more difficult as wafer diameter increases. This makes 12-inch SiC interposers both a technical challenge and a technological milestone.

Key Manufacturing Processes Explained Simply

Manufacturing a 12-inch SiC interposer involves many of the same steps as silicon interposers—but each step is more demanding due to the nature of the material.

Wafer preparation and thinning
SiC wafers are extremely hard. Thinning them to the required thickness without introducing cracks or excessive warpage requires highly controlled grinding and polishing processes.

Patterning and via formation
Interposers rely on vertical electrical connections. In SiC, forming these vias requires advanced dry etching or laser-assisted techniques capable of penetrating a very hard and chemically inert material.

Metallization and interconnects
Depositing metals that adhere reliably to SiC, while maintaining low electrical resistance and long-term stability, is a non-trivial task. Specialized barrier and adhesion layers are typically required.

Inspection and yield control
At 12 inches, even small defect densities can have a large impact on yield. This makes process monitoring and in-line inspection especially critical.

Together, these steps form a manufacturing flow that is more complex than traditional silicon interposer fabrication, but also far more capable in demanding applications.

System-Level Implications: More Than Just Packaging

The real value of 12-inch SiC interposers becomes clear when looking at the system level rather than individual components.

By integrating mechanical strength and thermal conductivity directly into the interposer, system designers gain:

• Lower junction temperatures for high-power devices

• Improved reliability under thermal cycling

• Greater freedom in system architecture and component placement

In practical terms, this means denser power modules, more compact high-performance computing systems, and improved durability in harsh environments such as electric vehicles, data centers, and aerospace electronics.

A Platform for Heterogeneous Integration

As semiconductor systems evolve, they increasingly combine logic chips, power devices, RF components, and even photonics within a single package. Each of these elements has different thermal and mechanical requirements.

12-inch SiC interposers offer a unifying platform that can support this diversity. Their material properties align naturally with wide-bandgap devices and high-power applications, making them especially attractive for next-generation heterogeneous integration.

Looking Ahead

12-inch SiC interposers are still at an early stage of adoption, but their trajectory is clear. They address fundamental challenges that cannot be solved by silicon alone, particularly in high-power and high-thermal-density systems.

Rather than viewing them as a niche solution, it is more accurate to see 12-inch SiC interposers as an enabling technology—one that bridges materials science, manufacturing innovation, and system-level design.

As advanced packaging continues to define the performance limits of modern electronics, the interposer is no longer just what connects the chips. In the case of SiC, it is becoming part of the system itself.