Proton exchange method and equipment for producing lithium niobate light waveguide

Abstract

The present invention is proton exchange method and equipment for producing lithium niobate light waveguide. The production process includes cleaning substrate, preparing mask, photoetching to form waveguide pattern, proton exchnage, annealing, end polishing, regulating waveguide and inspection. The present invention uses lithium benzoate doluted benzoic acid solution as proteon source, and has high lithium ion density and low hydrogen ion density and thus low reeaction speed, low lithium ion exchanging amount, and refraction index difference between the waveguide and the substrate. The annealing results in refraction index distribution ever suitable for coupling with fiber, less corrosion of benzoic acid, less faults in waveguide and low waveguide loss.

Description

technical field [0001] The invention relates to a method and device for manufacturing optical waveguide, in particular to a method and device for manufacturing lithium niobate optical waveguide by proton exchange. Background technique [0002] In recent years, with the rapid development of optical communication technology, people are ambitiously carrying out research and development of all-optical networks, and lithium niobate optical waveguide devices play an important role in it. Lithium niobate optical waveguide devices that can be widely used in optical communication systems include intensity modulators, phase modulators, couplers, optical switches and optical switch arrays, wavelength tunable filters, polarization controllers, etc. Without exception, these devices need to make optical waveguides on lithium niobate crystals, and use the electro-optic effect of lithium niobate crystals to change the physical parameters of the light waves in the waveguides to realize devic...

AI Technical Summary

Problems solved by technology

The existing proton exchange process uses pure benzoic acid exchange, the exchange capacity is large, H + Rapid accumulation on the surface, poor refractive index distribution, and low coupling efficiency; pure benzoic acid has a strong corrosion effect on the crystal surface, causing waveguide defects, resulting in the failure to reduce the insertion loss of the device; crystal lattice distortion in the waveguide area, Li atoms The loss is serious, the electro-optic coefficient is greatly reduced; the exchange reaction speed is fast, the process is not easy to control and adjust, the repeatability is poor, and the yield is low

Although combined with the annealing process, the refractive index distribution and electro-optical efficiency have been improved to some extent, but the effect is not very satisfactory

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