Can you explain the electrical properties of filled vias?
electrical properties of filled vias
As electronic components generate more and more heat, effective thermal management becomes increasingly critical for ensuring the long-term integrity of printed circuit boards (PCBs). This is why via-filling materials and processes are rapidly evolving to support greater energy efficiency and robust electrical performance.
In order to reduce temperature levels, it is crucial that the heat produced by circuit boards is channelled away from sensitive components and metal contacts. This is where copper-filled vias come in, which improve a PCB’s electrical and thermal conductivity, reducing power losses, and enhancing performance.
Vias are drilled holes in the surface of a PCB that are then filled with either conductive or non-conductive material. The plated copper in the via acts to carry signal transmissions between layers, but as such, these can become disrupted through various factors. Vias can also be impacted by the physical and environmental properties of the surrounding area in which they are located, such as interference from electromagnetic radiation (EMI).
As such, there is a growing need to create more efficient and reliable ways to connect different layers on a multi-layer board. Conductive via filling is a major technology that helps address these issues by enhancing current conduction between vias and other parts of the circuit board. In addition, a conductive via fill can also wick away excess heat from a PCB, extending its lifespan and preventing potential defects.
Can you explain the electrical properties of filled vias?
Typically, vias can be filled with both conductive and non-conductive materials to meet a range of design requirements. For example, a conductive via fill made with silver or copper will increase the conductivity of the via, making it more useful for transmitting signals across the board. However, the silver or copper can also exacerbate the thermal conduction of the via, so it may be more appropriate to use a non-conductive fill instead for a specific application.
In the case of copper-filled vias, a key benefit is that they can handle high amounts of electricity without affecting the board’s overall conductivity. This makes them suitable for applications where large currents must be moved from one side to the other, such as in the case of PCBs built for high-voltage levels.
The process of creating a conductive via fill can take some time, as the copper needs to be deposited using an electroless copper deposition step, which is time-consuming. There are also several additional steps in the process, such as curing and drying, which can add to the total manufacturing time. The good news is that non-conductive via fills are a much simpler process and often less time-consuming than the conductive copper-fill method. This means that a board maker can produce more circuit boards in a shorter amount of time. This is good news for manufacturers who are constantly looking to cut costs and improve production times while maintaining a high level of quality.