Patent ID: 6185355
Filing Date: 2001-02-06
Classification: G02B,G02F

Abstract:
An active integrated optic (IO) device, comprising(a) a crystalline material substrate having at least one surface;(b) an integrated optic circuit, including an optical waveguide and at least one electrode disposed in juxtaposition on said surface to provide at least one integrated optic region thereon;as characterized by:(c) said optical waveguide being formed in said surface by a two step proton exchange process comprising the steps of:(i) immersing said substrate for a period of time in a heated bath including at least 70% by weight of a strong acid, and(ii) cyclically differentially annealing said substrate by heating and cooling said substrate through at leasta first annealing cycle comprisingfirst heating said substrate through an up-ramp to a first elevated temperature above room temperature, andcooling said substrate from said elevated temperature through a down-ramp to a first low temperature which is at least seventy-five degrees C. lower than said elevated temperature, anda second annealing cycle subsequent to said first annealing cycle and comprisingfirst heating said substrate through an up-ramp to a second elevated temperature above room temperature and above said low temperature, andcooling said substrate through a down-ramp to a second low temperature which is at least seventy-five degrees C. lower than said second elevated temperature.