Method and apparatus for burying waveguide paths.

摘要

Optical waveguide paths are formed under the surface of a glass substrate by a method comprising (a) forming by ion-exchange a dopant ion path on a first substrate surface, (b) applying an electrode to the second surface, (c) contacting the first surface with a molten salt bath, and (d) applying an electrical field across the substrate to drive the dopant ions deeper into the substrate. The apparatus comprises means (37) for supporting the substrate (13') such that the first substrate surface (17') is in contact with the molten salt bath (10'). A porous electrode (19') is disposed on the second surface (18') of the substrate. A voltage is applied to the porous electrode and the bath to create the electrical field. The substrate supporting means (37) includes a planar conductive surface (42) for contacting the porous electrode (19'). A groove (41) extends around the periphery of the conductive surface, and means (40, 43) evacuates the groove and removes oxygen from porous electrode (19'). A glass insulating ring (35) can be affixed to the periphery of the second surface (18') to prevent salts from the bath (10') from migrating up the side surfaces of the substrate by capillary action. <IMAGE>