Manufacture of planar waveguides using sol-gel techniques
US7159421B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 2002 |
| Grant date | Jan 9, 2007 |
| Priority date | — |
| Expiry date | Mar 11, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2006/12097
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Silica sol techniques are described for making thick silica or silica based films useful for planar optical waveguides. The process involves coating of a colloidal silica sol onto a substrate, drying the sol, and consolidating the dried sol to form the planar waveguide. Coating is performed in a simple operation, either by dipping, or preferably by spin coating. In a preferred embodiment the substrate is coated with a wetting agent prior to spin coating. It is found that the wetting agent substantially improves the thickness uniformity of the layer.Thick waveguide layers may be produced by repeating the coating process one or more times to produce a layer with the desired thickness. Buried waveguides are produced by forming a doped core layer, patterning the doped core layer and using the coating technique of the invention to form the cladding material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.