Multilayer material and method of preparing same
US7901736B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2005 |
| Grant date | Mar 8, 2011 |
| Priority date | — |
| Expiry date | Oct 14, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31504
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention relates to a multilayer material deposited by ALD. A multi-layer structure of a high refractive index material is deposited on a substrate using ALD at a temperature below about 450° C. Advantageous results are obtained when a high refractive index material A is coated with another material B after a certain thickness of material A has been achieved. Thus, the B barrier layer stops the tendency for material A to crystallize. The amorphous structure gives rise to less optical loss. Further, the different stress nature of materials A and B may be utilized to achieve a final optical material with minimal stress. The thickness of each material B layer is less than that of the adjacent A layer(s). The total effective refractive index of the high refractive index material A+B being shall be greater than 2.20 at a wavelength of 600 nm. Titanium oxide and aluminium oxide are preferred A and B materials. The structure is useful for optical coatings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.