FPCs are available in readymade sheets and sizes. More often than not, your FPC supplier has the FPC of your preferred thickness in stock or can quickly obtain it. But did you know that you can specify your FPC thickness? 

The thickness ranges from 0.2mm to 6.3mm in hundredths of millimeter increments. Yes, you read that right! There are two-layer FPCs that are as thin as 0.2mm! As FPC thickness options appear on the specification tab of your designer’s FPC workspace, all you have to do is select the custom thickness option. 

This prevents your design from being panelized by other designs. Therefore, minimum FPC area charges will apply. When creating custom thickness, the FPC fab starts with a set of common core and prepreg thicknesses, then combines them in the necessary sequence, along with copper foil, solder mask, and copper plating thickness to reach the desired final thickness.

However, custom thickness is only specific to your FPC, and it will be designed only for you. By stating your thickness preference, your manufacturer will let you know whether the design is possible.