What is Considered A Microvia PCB?

Microvia PCBs (Printed Circuit Boards) are one of the advanced circuit boards used in various high-tech applications. They are also known as HDI (High-Density Interconnect) boards. Microvia PCBs have a higher number of I/O pins and smaller features than other types of PCBs. Let's discuss what type of PCBs are considered as microvias PCB.

What Makes Microvia PCB Unique?

Microvia HDI PCB is a unique type of printed circuit board that uses microvias to connect the different layers of the board. Microvias are tiny holes drilled into the board and then filled with copper to create the electrical connection between the layers. This type of board is used in high-density applications where space is at a premium, and the board needs to be able to handle high speeds and large amounts of data.

Micro via PCB is a printed circuit board that uses micro vias to connect the different layers of the board. Micro vias are tiny holes drilled into the PCB and are used to connect the different layers of the board.

Micro vias are tiny holes drilled into the PCB to connect different layers of the board. They can be as small as 0.004" in diameter, about one-tenth the size of a human hair!

The main advantage of using microvias is that they allow for a much higher density of connections than traditional vias. This means that more components can be placed on the board, and the board can be made smaller. Microvias also have a lower resistance than traditional vias, which means they can handle higher speeds and larger amounts of data. These vias are commonly made using a process called laser drilling.

Laser Drilling

In this process, a high-powered laser is focused on a small area of the PCB and drills through the layers of copper and substrate material. The diameter of the micro via is determined by the size of the laser beam and the speed at which it is moved across the surface of the PCB.

The laser drilling process can be divided into four steps:

1. Pre-Drilling: The laser beam is focused on the surface of the PCB, and a small hole is drilled through the top layer of copper. This step ensures that the subsequent drilling steps are aligned correctly.
2. Drilling: The laser beam is focused on the surface of the PCB and drilled through the top layer of copper and the substrate material.
3. Clearing: The laser beam is used to remove any debris that the drilling process has created.
4. Post-Drilling: The laser beam is focused on the bottom layer of the PCB and drills through the copper and substrate material. This step ensures that the via is properly connected to the bottom layer.

The microvia drilling process can be completed in a matter of seconds and does not require special skills or training. This makes it an ideal solution for creating small vias in high-density PCBs.

Microvias Over Through Hole Vias

There are differences in construction and electrical performance between a microvia over through hole (VOF) and a regular via. Let's take a closer look!

As their name suggests, microvias are much smaller than regular vias. They typically have diameters ranging from 0.006" to 0.004", while regular vias have twice as large or more diameters. The smaller diameter of microvias results in several important differences in their construction and electrical performance as compared t through-hole vias.

Precise Alignment

First, microvias are drilled using a laser rather than a mechanical drill bit. This results in much more precise alignment and smaller diameter tolerances

Better Electric Conductivity

Second, micro vias are typically filled with a conductive material such as copper or gold, while regular vias are not. This filling provides better electrical conductivity and prevents oxidation of the exposed metal surfaces.

Shallow Depth

Third, microvias generally have a shallower depth than regular vias. This is due to the smaller diameter and the fact that they are typically filled with a conductive material.

Improved Signal Integrity

Fourth, the walls of microvias are much thinner than regular ones. This allows for better signal integrity and less crosstalk.

Higher Aspect Ratio

Finally, microvias have a higher aspect ratio than regular vias. This means that they are narrower and taller in proportion to their diameter. Higher aspect ratios are more difficult to drill and require special manufacturing processes.

Due to these differences in construction and electrical performance, micro vias are well-suited for use in high-speed and high-density circuits.

They are also becoming increasingly popular in consumer electronics applications such as mobile phones and tablets, where their small size and improved electrical characteristics are particularly advantageous. Let's have a look at some other advantages and disadvantages of microvia!

Advantages and Disadvantages of Microvia PCB

Advantages

This type of PCB is becoming increasingly popular because it offers several advantages over traditional PCBs.

One of the biggest advantages of micro via PCB is that it offers a higher density of interconnections than traditional PCBs. This means more components can be placed on a micro via PCB, and the board can be more densely populated with components. This makes micro via PCBs ideal for high-density applications such as mobile phones and laptops.

Another advantage of micro via PCB is that it offers improved thermal performance. The smaller vias offer a lower resistance path for heat to travel, which means that the components on the board will run cooler. This is especially important in applications where the PCB will be exposed to high temperatures, such as automotive applications.

Micro via PCBs also offers improved electrical performance. The smaller vias result in a shorter path for electrons to move, making the electrical signals less likely to be distorted. This capability of Microvias is useful in applications where the PCB will be used to carry high-speed signals, such as in video and audio applications.

Disadvantages

One of the main disadvantages of micro via PCB is that it can be more expensive than traditional PCBs. This is because the manufacturing process for micro via PCBs is more complex, and the boards are typically thinner than traditional PCBs. As a result, micro via PCBs often cost more to manufacture.

Although micro via PCBs can be more expensive to manufacture, they offer several advantages that make them ideal for use in various applications. Micro via PCBs are becoming increasingly popular in the electronics industry and are expected to continue gaining popularity.

Final Thoughts

If you are looking for an advanced type of PCB that offers all these benefits, then you should consider using microvia PCBs in your next project. Microvia PCBs are available in a variety of sizes and shapes. You can choose the one that best suits your application. You can also get them customized according to your specific requirements.