Under normale PCB design conditions, the following factors mainly affect the impedance by PCB manufacturing:

1. The thickness of the dielectric layer is proportional to the impedance value.

2. Dielectric constant is inversely proportional to impedance value.

3. The thickness of copper foil is inversely proportional to the impedance value.

4. Line width is inversely proportional to impedance value.

5. Ink thickness and impedance value inversely proportional.

So we should pay attention to the above points when controlling impedance.