Copper & Epoxy Filled Vias

Copper-Filled Microvia and Epoxy-Filled Via PCB Solutions

Topline Circuit manufactures PCBs with copper-filled microvias and epoxy-filled vias for HDI, micro BGA, via-in-pad, and other space-constrained designs. These filled vias increase routing density, support reliable interlayer connections, and create a flat surface for component assembly.

Copper-filled microvias provide strong electrical connections and transfer heat to internal copper planes. Epoxy-filled vias seal the hole and create a smooth surface for components placed directly over the via. Conductive or non-conductive epoxy can be selected based on the electrical, thermal, and assembly requirements.

Our engineering team supports layout review, DFM analysis, PCB fabrication, and assembly. We review via structures, fill materials, and plating requirements to improve manufacturability and reduce filling or surface-flatness issues.

Overview of Copper Filled Microvias

Copper filled microvias are advanced PCB structures designed to improve layer connections, thermal management, and routing density. By filling laser-drilled microvias with copper, manufacturers can achieve stronger interlayer connections and better heat dissipation.

The manufacturing process includes laser drilling, electroless copper plating, imaging, and precision electroplating to create reliable filled via structures. Due to the high precision requirements and additional processing steps, copper filled microvias may increase PCB manufacturing complexity and cost.

Similarities and Differences Between Copper and Epoxy Filled Vias

Copper filled vias and epoxy filled vias are both used to improve PCB performance by enhancing layer connections, supporting high-density routing, and optimizing component placement. However, each technology provides different advantages based on design requirements.

Copper filled microvias are commonly used in HDI and high-density PCB designs. They allow trace routing to inner layers for fine-pitch components such as BGAs and provide an effective thermal path to copper planes for improved heat dissipation.

Epoxy filled vias are mainly used when a flat PCB surface is required for component placement, especially for designs with components mounted directly over vias. Conductive and non-conductive epoxy fills can support compact designs while providing different levels of thermal performance.

Full-Service PCB Support

Filled via PCB technology is widely used in high-density and high-performance electronic applications where reliable connections, thermal management, and compact designs are
required.

Common applications include:

Telecommunications — Supporting high-speed signal transmission and compact communication equipment designs
Aerospace — Providing reliable PCB structures for demanding environments and mission-critical electronics
Medical Devices — Enabling complex PCB layouts with improved reliability and space efficiency
Automotive Electronics — Supporting advanced vehicle systems with durable and high-performance circuit designs
Consumer Electronics — Helping achieve smaller form factors while maintaining electrical performance
Industrial Equipment — Improving PCB reliability for control systems and automation applications
Energy Systems — Supporting power electronics and complex circuits requiring stable performance

Overview of Epoxy Filled Vias

Epoxy filled vias use epoxy resin to fill plated through holes or vias, creating a flat and reliable surface for advanced PCB designs.Depending on the application requirements, the epoxy material can be either conductive or non-conductive.

Epoxy filled vias are commonly used for:

Component Placement — Allowing components to be mounted directly over vias, which helps save PCB space and supports high-density layouts

Surface Planarity — Creating a smooth PCB surface for fine-pitch components and advanced assembly processes

Conductive epoxy filled vias can also provide additional thermal paths by transferring heat away from high-power components, such as sensors, RF devices, and GaN-based power amplifiers.

The manufacturing process typically includes via plating, epoxy filling, curing, and copper capping to create a sealed via structure.

Compared with copper-filled vias, epoxy-filled vias provide a flexible and cost-effective option, but their thermal performance depends on the type of epoxy material used.

Your Copper and Epoxy Filled Via PCB Manufacturer

Topline Circuit manufactures PCBs with copper-filled microvias and epoxy-filled vias for complex and high-density designs.

Copper-filled vias improve thermal transfer and electrical conductivity, while epoxy-filled vias create a flat surface for via-in-pad assembly.

Our engineering team reviews the via structure, materials, and manufacturing requirements to support reliable PCB fabrication and assembly.

Engineering Support for Copper and Epoxy-Filled Vias

Topline Circuit supports copper-filled microvias and epoxy-filled vias for HDI, via-in-pad, and high-density PCB designs.

Our engineers review the via structure, fill material, plating, and surface requirements to improve manufacturability, thermal performance, and assembly reliability.