Patent ID: 6547976
Filing Date: 2003-04-15
Classification: G02B

Abstract:
A method for manufacturing a planar optical circuit on substrate, the method comprising the steps of:forming a core layer on the layer; creating a mask on the core layer, the mask being formed of a refractory material, the mask having a first portion defining a first pattern and a second portion defining a second pattern, the first pattern corresponding to a desired pattern to be formed in the core layer and the second pattern corresponding to one or more alignment marks; etching the core layer through the mask to expose portions of the substrate not overlaid by the first portion and the second portion of the mask; removing the first portion of the mask to create exposed portions of the core layer corresponding to the desired pattern in the core layer, while leaving the second portion of the mask in place; partially oxidising the second portion of the mask; and forming an overclad layer on the exposed portions of the core layer and the second portion of the mask.