How is the coating applied to the pan?

It depends what the pan is made of, with a comparatively soft metal like aluminium, the bond between the coating and the metal is so strong that it will stand up to considerable stress - so aluminium pans are usually made by pressing the pan shape from an aluminium disc already coated with the PTFE. With harder metals, like steel or cast iron, the bond between the coating and the metal isn't as strong, so the coating is sprayed on after the pan has been pressed.

Then the coating is cured at very high temperature - more than 350ˆC this makes the coating stratify into layers: the binding agents sink, and adhere to the metal body of the pan, while the PTFE and the hardening agents rise to the surface to create the non-stick layer.