Stackups

We have recently slightly changed our stackups. The previous stackups no longer aligned with what our PCB manufacturing partners consider standard. We've now revised them to be more representative of current manufacturing capabilities.

That said, the older stackups are still viable, they're just no longer part of our standard set. If needed, they can still be used by selecting them as a custom stackup, and this won't affect the pricing. In fact, we've expanded our offering to include more options, including variants with 2oz and 0.5oz copper, giving users greater flexibility.

Standard stackups

We provide standard stackups for boards with 1-10 layers. Please see here for a list of our standard stackups.

Below is more information about our standard stackups.

Prepreg dielectric constant

Solder mask parameters

Core dielectric constant

Core dielectric constant: 4.2

As we work with multiple board fabrication vendors, we cannot guarantee whether the core layers will be made from a single or multiple layers. However, our fabrication partners are highly experienced and will carefully consider your design requirements to determine the most suitable option.

We understand that in specific cases such as those involving micro-drilling the difference between a one layer or multi layer core can be important. Please rest assured that our partners will take your design and requirements into account and fabricate the boards accordingly.

If your board has more than 10 layers, we cannot guarantee the exact stackup configuration on a layer-by-layer basis. In these cases, we use a freebuild approach. This means the overall copper weights, board thickness, and dielectric materials will match your specifications, but we cannot commit to precise individual layer thicknesses or the exact materials layer by layer.

Note on plated vs base copper

The core thickness includes the dielectric plus the base copper foil on each side (typically 35 µm for 1 oz). However, when outer layers are finished, additional plated copper is added after lamination—this plating (~18 µm per side) is not part of the core and therefore not included in the core-thickness figure. In short, "Core" refers only to the laminate (dielectric + base copper). The additional plating copper used on outer layers is applied post-lamination and not counted in core measurements.

Custom stackups

A custom stackup is a stackup that differs from one of our standard stackups and is not specified simply by selecting the board thickness and copper weights. All custom stackups have to be specified using the 'None standard' button on the board view of the project page, even if the stackup is already defined in your design files or one of your layers.

Custom stackups override the default selection of board thickness, copper weight and material.

To add a custom stackup, please specify, in the required order, information such as the following for all layers:

• Layer Name or position (1, 2, 3 etc)
• Layer copper weight (ie 1oz, 2oz etc)
• Material type (ie FR4, Rogers, or more specific 370HR)
• Dielectric Separations
• Overall Board thickness

Also include any other relevant information.

Please note that we may not use the exact requested materials but rather attempt to satisfy the properties of your stackup with the materials we have on hand. If you require a specific material to be used, make this clear in your requirements.

Once you have specified a custom stackup, your project will be marked for manual quoting and you will be notified once your quote is ready.

Impedance control

Please note that if your design has specific impedance requirements, you must add impedance control to your project to ensure the boards meet those specifications.

Our standard stack-ups are carefully prepared based on common configurations, but minor variations can occur due to differences in materials, processes, or tolerances between PCB manufacturing partners. These variations are typically negligible, but should be reviewed for critical applications.

Adding impedance control to your project will ensure that the stack-up is adjusted accordingly and that your impedance requirements are met.