Are Aluminum Oxide PCBs expensive?
Compared to standard rigid PCBs (FR4), Al2O3 PCBs are more expensive. However, it is competitive with other high-end substrates (Rogers, Copper metalcore) and usually performs better thermally or in design possibilities. Also, thanks to its material properties, it allows for savings on other parts of the module.
To control costs, we recommend keeping the ceramic PCB small and integrated.
Are ceramic PCBs able to pass reflow and be used in SMT & pick-and-place machines?
Yes, both are possible but be aware that your standard reflow profile likely needs to be updated as the substrates as more thermally conductive.
Can Al2O3 PCBs be multi-layer?Â
Yes, we can deliver multilayer ceramic circuits up to 4 layers. More layers might be possible, please enquire.
How big can Alumina boards be?
Our prototyping line serves a maximum of 100x80mm / 3.9″x 3.2″.
For normal production 125mmx125mm or 5″x 5″ panels are standard but we can accommodate larger boards up to 180mm x 180mm (7″x 7″) or even larger. please enquire via contact us.
Is there also a solder mask layer, surface finish, and silkscreen possible?
Yes, depending on your requirements (operating temperature, environmental hazards, …) we can supply regular solder resist or glass-based solder masks. Also, silkscreen is possible. Surface finish depends on the metalization but generally immersion tin, silver, ENIG, and/or ENEPIG are available. We will help you to select the right specifications so it fits your application and design.
What should I take into account when designing circuits layouts for a ceramic board? What are your design rules?
You can download our design rules on this page under ‘design rules’ which will give already a lot of information. Detailed design for manufacturing checks will be done before we start production. If you are still unsure whether your design is suitable for Ceramic PCB production. Please contact us and we’ll be happy to support you.
What is the difference between regular (rigid) PCB production and ceramic PCB?
Rigid PCBs are made using a retractive method using photolithography and etching. Ceramic PCB can be made using a variety of additive and retractive methods like direct plating copper, direct bonding copper, thick film printing, thin-film printing, LTCC, HTCC, … which are all significantly different than standard PCB production. Selecting the right production process depends and the requirements and specifications of the design. We have the necessary experience and will support you so you can focus on what you need in the end rather than how to get it.
Please explain why it is claimed that Alumina Oxide PCB (Al2O3) has good thermal conductivity compared to metal core PCB (IMS) when you know Al (160 W/mK) and Cu (>200 W/mK) have a much higher thermal conductivity compared to Al2O3 (22 W/mK)?
Al & Cu have indeed high thermal performances but the dielectric layer which separates the metal core from the conductive traces will increase the thermal resistance significantly. Both the dielectric by itself (usually <3 W/mK thermal conductivity) and the interface resistance will reduce the total thermal performance. Depending on the thickness of this layer (<10 W/mK) the thermal conductivity of the board can be reduced by 70-90%!
Alumina 96% (Al2O3), on the other hand, is a dielectric material and thus traces can be placed directly onto the board eliminating any loss in conductivity resulting in less overall thermal resistance. Furthermore, Alumina can handle multilayer designs without losing thermal conductivity.
Our experience learns us that alumina circuits especially outperform metal core PCB in smaller integrated designs where space is limited and where heat can’t be properly spread on the top side of the board.
