Microvias
With newer technology requiring smaller components, it is essential to find ways to increase the wiring density on a printed circuit board. One way is through the use of microvias. Microvias are small blind holes that allow higher-density PCBs to be manufactured and connected together. These tiny vias are drilled through the layers of the PCB, reducing the space needed for traditional pads and conductors to transfer data from one layer to another.
Compared to the standard vias found on most conventional PCBs, a microvia has a much lower capacitance and inductance. This is because they do not contain stubs, which can resonate and pick up signals from neighboring pads or traces. This reduces signal transmission loss and crosstalk interference.
Microvias can be made in a variety of ways. They can be stacked or staggered, and they can be filled with copper or unfilled. They can also be offset or buried. Stacked and offset microvias are useful in achieving high-density layouts, especially when used with fine pitch BGAs or CSPs. Buried microvia are a great tool to use for high-reliability applications, as they can reduce signal reflection and allow for a more robust connection between components.
How Microvias Can Be Used in Military Applications
When designing a PCB with microvias, the designer must carefully select the laminate and materials to ensure they can be fabricated with the fabrication process. They must also ensure that the underlying substrate has sufficient thickness to support the vias. This is important because if the underlying substrate is too thin, it can cause microvia reliability issues.
The most common issues associated with a PCB with microvias are related to thermal cycling. This can cause the PCB to expand and exert stress on the copper plating inside of a via. Typically, this occurs at the interface between two stacked vias or at the bottom of a buried microvia where it meets with the metallurgical junction of the top pad.
Laser drilling is often used for microvia production. This is due to the positional precision of laser drills as well as their ability to handle a variety of materials and hole depths. While photolithography is a viable alternative to laser drilling, it is usually reserved for higher-via-density products. In addition, it can be difficult to achieve the required dimensional tolerances for a microvia. Therefore, laser drilling is still the preferred method of making a PCB with microvias. To learn more about using microvias in a high-density layout, contact a trusted PCB manufacturer like PCBONLINE today. We offer high-density layout and assembly services for a wide range of industries. If you are interested in purchasing a PCB with microvias, please contact us from the table on the right. We look forward to hearing from you! PCBONLINE is dedicated to promoting the latest technologies in the electronics industry. If you have any questions about the topics in this article, please email us at [email protected] or call us at (877) 660-4653. You can also get a free quote on the PCB you need by clicking the button on the right!