Rush PCB UK: Experts in Blind and Buried Via Technology

As an experienced printed circuit board manufacturer in the UK, Rush PCB UK offers PCB manufacturing services for boards with blind vias, buried vias, and microvias. We have professional and dedicated personnel for designing these special vias, which are necessary for interconnecting different layers in multilayer PCBs and HDI boards.

Blind, Buried, and Micro-Via PCB Manufacturing Services

Modern electronic equipment, being highly complicated and miniaturized, requires special high-density printed circuit boards with multiple layers. Most of these PCBs are HDI or High-Density Interconnect boards with closely-packed thin traces, where regular through-hole vias are an overkill.

In keeping with the high-density nature of the boards, we use very small blind, buried, and micro-vias for interconnecting various layers of the board. The following table illustrates the differences between regular and HDI vias:

What Are Blind Vias, Buried Vias, and Microvias in PCB Design?

While designing multi-layer PCBs, it is often necessary to interconnect different layers including the top- and the bottom-most layers to achieve proper functionality. Earlier, in regular PCBs, through-holes provided this connectivity. To create these through-holes, it was necessary to drill holes through the entire thickness of the board and electroplate it to provide the electrical connection.

As is evident from the table above, the drill size required for the through-holes is about 8 mils at their smallest. For high-density boards, this is too large, as we offer holes below 8 mils. We offer various types of vias, such as:

Blind Vias

These vias originate on either the top-most or the bottom-most layer and terminate on an internal layer, interconnecting any other layer in between, as necessary. This means you can see only one end of a blind via.

Buried Vias

These vias originate at an inner layer of the board and terminate on another inner layer, while interconnecting any other layer in between, as necessary. This means you cannot see either end of a buried via from the outer surface of the PCB.

Micro-Vias

Typically, we used mechanical drill bits to drill the via holes. But with hole sizes going below 6 mils, it is difficult to handle such fine drill bits, as they are prone to breaking. Therefore, we use fine laser beams to generate the holes. The laser beam ablates or melts the copper layer and the substrate below it until it reaches the bottom copper layer. That means, most micro-via holes have an aspect ratio of 1:1. To provide connectivity to other layers, microvias can be stacked or staggered, depending on routing and design requirements.

Benefits of Blind, Buried, and Micro-Via Technology

Advanced technologies allow achieving a very high density of routing for modern HDI boards. For instance, breaking out interconnections for high-density BGAs is only possible with advanced via technologies, as these components have upwards of 250 pins with 0.4 mm pitch. Other benefits of using advanced technologies are:

• Increased routing density — supports compact PCB layouts
• Smaller form factor — helps reduce overall board size
• Improved electrical performance — supports shorter signal paths and better signal integrity
• Enhanced reliability — improves via performance in high-density designs
• Greater design flexibility — supports fine-pitch BGAs and advanced component layouts

Applications of Blind, Buried, and Micro-Vias

Any electronic equipment that uses high-density PCB layouts requires blind, buried, and micro-vias. These include wearables, smartphones, tablets, laptops, medical devices, automotive electronics, aerospace systems, and other miniature electronic products.

Why Choose Rush PCB Ltd for HDI Via Manufacturing?

Rush PCB Ltd has been manufacturing high-density and other boards for the last two decades, and is one of the pioneers in the PCB arena. We offer many types of PCBs for various applications, and our HDI boards with advanced via technologies are trusted for use in fields like aerospace, military, communication, and computers.

We offer precision and quality assurance you can trust, as we follow international standards for manufacturing our PCBs, and Rush PCB Ltd is:

• Member of IPC
• ITAR registered
• ISO 9001:2015 Certified
• AS9100:2016 Certified

We offer a single-window approach to our customers, and you can simply offload your requirements on our portal. We will provide you with end-to-end support, from design to delivery.

Our Blind, Buried, and Micro-Via PCB Fabrication Capabilities

We follow IPC-6012 for copper plating requirements for surface and holes for our PCBs, meeting Class 1, 2, and 3. Our manufacturing capabilities for blind, buried, and micro-via fabrication are as follows:

Industries We Serve with Advanced HDI PCBs

Industries using miniaturized and high-performance products widely use our advanced HDI PCBs. Among these industries are:

• Consumer Electronics — Compact consumer gadgets like wearables, tablets, and smartphones.
• Automotive Electronics — Electric power-trains, advanced driver assistance systems, in-vehicle infotainment.
• Medical Devices — Diagnostic imaging tools, blood glucose monitors, and hearing aids.
• Aerospace and Defense — Military systems, radars, avionics, and other equipment working under shock, vibration, and extreme temperatures.

Request a Quote for HDI Via PCB Manufacturing

Need blind, buried, or micro-via PCB manufacturing for your next HDI project? Contact Rush PCB UK today to discuss your PCB design, confirm via feasibility, or request a fast quote.