Embodiments of the invention provide a conductive coating on an insulator of an x-ray tube and a method for applying the conductive coating. The method may use a first process, such as brazing, to join a support to the insulator and a second process, such as vapor deposition, to apply the conductive coating onto a substrate surface of the insulator. The second process may be carried out after the first process without any damage to x-ray tube insulator assembly.