NCAB has a long experience of building HDI boards, and the factories we work with have a deep expertise in producing HDI PCBs for different industry applications.
This, combined with our worldwide technical organization, bring a comprehensive knowledge of the requirements and manufacturing methods required for successful HDI products.
IPC-2226 defines HDI as a printed circuit board with a higher wiring density per unit area than conventional printed circuit boards (PCB). They have finer lines and spaces ≤ 100 µm / 0.10mm, smaller vias (<150 µm) and capture pads <400 µm / 0.40mm, and higher connection pad density (>20 pads/cm2) than employed in conventional PCB technology. There are different types of HDI features, type I, type II and type III.
The graphic below shows the main structures – type I, type II and type III as defined in IPC-2226.
Construction terminology to define the degree of HDI construction:
For information about our technical capabilities for HDI PCBs, read more at our Technical Capability page. You will also find information relating to materials, other PCB technologies or product types which we currently produce, as well as some of the tolerances which we can achieve.
Below you can learn more about different aspects of design and HDI PCBs like design tips, design guidelines and design trends.
Nothing affects the PCB’s cost and quality as much as the initial design. Here you find some useful information about common design problems, what production problems they can cause – and most important – the best solution to avoid them!
Don´t hesitate to contact us if you need help with your PCB design – we are happy to help!
More than 30% of the Gerber data we receive do have some issues. They can contain ambiguous information, errors, design rule conflicts, missing information and contradictions between the data and specifications. To prevent that it gets wrong from the start, we have put together our design guidelines, to use as a checklist. This is an extract from our PCB design guidelines for HDI PCBs.
The whole design guideline can be downloaded for free.
IPC-4761 TYPE VII PLUGGING / VIPPO / POFV
Valid only for the outer phase of a buried core which needs cap plating – typically when a microvia is stacked on a buried hole.
For design tighter than this, please consult your local NCAB technical contact to review specific projects case by case.
A. Minimum copper wrap distance 25 um for class 1, class 2 and class 3
B. Minimum copper wrap thickness 5 um for class 2 and class 3
C. Minimum cap plating 12 um for class 3, minimum cap plating 5 um for class 2
We not only have design guidelines for HDI PCBs, but also for Multilayer PCB, Ultra HDI PCB, Flex / Rigid-Flex PCBs, Semi-Flex PCB, Copper coin, Via Protection and Stackups and Impedances.
In a couple of blog posts we have delved into the key factors for a successful production of HDI PCBs, and scrutinized design trends for HDI PCBs. Read an excerpt below.
The miniaturization of electronic components pushes the evolution of printed circuit boards towards complexity that was unthinkable only a few years ago. The circuit boards needs more functions and performances all while being thinner and lighter. This requires a very rigorous design and production process. To develop this type of circuit boards, we need solutions for a greater density of connections and more layers in the printed circuit board.
The increasingly narrow design means less space available for routing, which results in thinner tracks and gaps with through holes of increasingly smaller diameter.
A couple notes on HDI designs:
When the project is being taken to extremes, it is clear that the entire design process must follow some necessary guidelines, from the designer to the PCB supplier.
There are two key factors for the successful production of HDI PCBs: first, making the right choices at the design stage, and then carefully choosing the factory that can support the specific technical demands of the project.
Whether it’s consumer electronics, computers, automotive or medical technology, the overall trend is reduction in size. Not just through a reduction in actual or finished product size, but also as the components themselves are becoming smaller, so the assemblies must be more densely packed and use smaller features.
The onset of these increasingly sophisticated electronic products has led to more advanced PCBs becoming more commonplace. The specifications here require high-density interconnect (HDI) solutions with greater number of layers, and more connections both on the surface and inside the PCB, utilizing finer conductor widths and narrower spaces between them.
Example of buildup of HDI PCB.
The increased number of layers, together with the microvia technology, also requires the use of thinner prepegs and cores than in conventionally manufactured boards which also leads to increased demands upon the factories.
Use our design guidelines to get your PCB design right from the start.
Please contact your local NCAB Group company if you need further information or assistance, we are happy to help you.
