Looking back at Altium Roadshow 2022

Altium Roadshow 2022 fell at the beginning of February this year. The planned meeting with the opportunity to meet in person in Brno was eventually cancelled due to the adverse covid situation and moved purely to the online environment.

The organizing Brno-based company RETRY invited Gatema PCB to present, among other things, to answer questions about PCB technology and production, but also to give the audience a practical introduction to the topic of filling and countersinking PCB holes. These technologies now can be solved directly in Altium Designer and the introduction to the manufacturing process made it easier to understand, what all will need to be configured, when creating a drawing so that the subsequent production has all the necessary data for smooth processing.


HDI boards hole filling

Hole plugging and filling is used against solder residues or other kinds of dirt in holes. This is especially important for critical interconnects, typically under BGA. The hole filling process is a frequent step in the production of HDI (high density interconnect) boards.


1. One of the advantages when vial are fille is that vacuum can then usedduring the assembly of electronic devices.

2. Using copper or heat conductive paste in the filling process will ensure better heat dissipation.

3. By filling the holes, damage to the PCB is avoided, the board becomes more durable and can then withstand higher voltages.

4. Filled holes allow the use of via-in-pad technology and save board space.




Pic. Visible subsurface moisture expansion including PCB deformation


Then we explained to the customers the process of manufacturing the filled holes and showed them why it is more advantageous to choose type VII instead of other fillings (via filling - type V and IV).

Type VII used in Gatema PCB

Type VII filling, which is the most used in Gatema PCB, was the one that received the most time. A simple cartoon model was used to explain the sub-steps of production and the advantages of this process. In Type VII filling, the two-sided filling of the already plated board is done at the same time before the actual PCB fabrication.


výroba 7

1. drilling

2. forging

3. filling holes

4. grinding

5. drilling

6. punching

7. etching + non-soldering mask


Pic. PCB type VII hole filling

The advantage of filling the plate with Type VII, compared to filling the plates with Type V and VI, lies in the price. Both types V and VI with completely filled holes are, especially in prototyping, incomparably more expensive, because producer has to change standardized processes. As a result, they require more manufacturing steps, plus lighting and etching. There are also more problems with surface flatness. Therefore, a PCB with Type VII fill is in all respects of higher quality and more reliable.

In order to give the participants comprehensive information, the practical part of the production presentation was followed by a demonstration of the via filling setup in Altium.



The next input was a presentation and practical information on PCB embedding, given by Radim Vítek on behalf of Gatema. He presented the tools used not only for countersinking, but also for chamfering of connectors. The 6 mm diameter countersink tool has three variants of drill tip chamfers, standard 90°, 120° and 140°.



Pic. Countersink ø 6 mm

He also introduced the counterbore options (for flat head screws). For this technology, we use a tipless milling tool, which we call a 3D/recessed milling tool, as shown in the B model below.




Pic.     A – countersink hole       B – counterbore hole


Data preparation

The manufacturer must obtain precise information from the contracting authority on the requirement for recessing. Ideally, all recorded in the data. When creating a backfill design, the best way is to have filled vias in a special layer. Alternatively, the specification can state what diameter of drill bit the holes are to be filled to. If the customer asks for filled holes and does not specify them in any way, then we will automatically fill all holes up to a drill diameter of 0,45 mm.

When preparing data in ODB++, the countersinks have their own layer. In the PCB drawing, you need to show the dimensions of the countersunk hole, including the side view. Finally on fabrication, it was noted that both the countersinking and milling can be plated (3D plated mill).

To make the fabrication seamless, it is very much dependent on the supplied PCB fabrication documents. More and more parameters are entering into the specification, so for anyone who is unsure of how to prepare the data for flawless PCB manufacturing, we have a technical sheet and PCB designer's guide ready on the web.



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Ondřej Horký
Sales Manager