Redistribution Layers (RDL) in Multi-Chip Modules

ED2 Corporation is working in the area of heterogeneous integration of chips and dies into fused silica packaging for best performance. We have branded our technology Advanced Glass Packaging Technology (AGPT?). Our knowledgebase starts with the fabrication/wafer level, where the team has worked for years on the chemistry and processing of fused silica, and has evolved into higher layers of value at the module level.

In a multi-chip module (MCM), redistribution layers (RDL) serve several important purposes:

Interconnection: One of the primary purposes of redistribution layers is to provide a means of connecting the individual chips within the MCM to each other and to external components. These layers contain a network of metal traces that route signals and power between the different chips and connect them to the package's external pins or connectors.

Signal Routing: RDLs facilitate the routing of high-speed signals between chips, ensuring that data can be transmitted quickly and reliably. They often include features like controlled impedance traces and signal shielding to maintain signal integrity.

Signal Decoupling: RDLs can include capacitors and other passive components that help to decouple the power distribution network, reducing noise and ensuring stable power delivery to the chips. This is particularly important for maintaining the performance of sensitive analog or high-frequency digital circuits. Many of ED2's applications are high frequency RF, some including emitters, and this area is critical for reducing noise and bringing performance.

Power Distribution: RDLs distribute power from the package's external power pins to the individual chips. They ensure that each chip receives the appropriate voltage and current to operate correctly.

Thermal Management: In addition to electrical connections, RDLs can incorporate thermal management features such as heat spreaders, vias, and thermal vias to dissipate heat generated by the chips. Efficient heat dissipation is critical for preventing overheating and maintaining the reliability of the MCM. ED2 has mastered the use of copper-filled through glass vias (TGV) for the purposes of heat dissipation.

Size and Form Factor Reduction: RDLs allow for the stacking of chips in a compact manner, reducing the overall footprint of the MCM. This is especially beneficial in applications where space is limited, such as mobile devices and miniaturized electronics.

Integration of Heterogeneous Components: MCMs often integrate chips with different functions and technologies, such as microprocessors, memory, sensors, and communication interfaces. RDLs enable the seamless integration of these heterogeneous components into a single package.

Manufacturability and Yield Improvement: RDLs can simplify the manufacturing process by allowing for the integration of tested and known-good-die (KGD) chips. This can improve overall manufacturing yield and reduce costs.

In summary, redistribution layers in a multi-chip module play a crucial role in interconnecting, powering, and managing the thermal aspects of multiple integrated chips within a single package, enabling the creation of complex and high-performance electronic systems in a compact form factor.

Reach out to us at ED2 to learn more about creating MCMs and other products in glass.