Methods of producing slanted gratings with variable etch depths
US10823888B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 2019 |
| Grant date | Nov 3, 2020 |
| Priority date | — |
| Expiry date | Nov 12, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0026
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Methods of producing gratings with trenches having variable height are provided. In one example, a method of forming a diffracted optical element may include providing an optical grating layer over a substrate, patterning a hardmask over the optical grating layer, and forming a sacrificial layer over the hardmask, the sacrificial layer having a non-uniform height measured from a top surface of the optical grating layer. The method may further include etching a plurality of angled trenches into the optical grating layer to form an optical grating, wherein a first depth of a first trench of the plurality of trenches is different than a second depth of a second trench of the plurality of trenches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.