US 11,079,543 B1 · Isotropic etchback method of linewidth tailoring multilayer dielectric diffraction gratings for improvement of laser damage resistance and diffraction efficiency

Abstract

A method of fabricating a multilayer dielectric (MLD) diffraction grating by providing a multilayer stack having a grating layer, and anisotropically etching the grating layer to form grating lines having an initial lineheight, an initial linewidth, and an initial grating duty cycle, that are greater than a target lineheight, a target linewidth, and a target grating duty cycle, respectively. An isotropic wet etch solution is then used to etch back the grating lines to the target lineheight, the target linewidth, and the target grating duty cycle so as to minimize electric field intensities and maximize diffraction efficiency for a given set of MLD illumination conditions.

Claims6

Dependent claims

A method of fabricating a multilayer dielectric (MLD) diffraction grating, comprising:

providing a multilayer stack having a grating layer;
determining a target lineheight, a target linewidth, and a target grating duty cycle of the MLD diffraction grating to be fabricated;
selecting an initial lineheight, an initial linewidth, and an initial grating duty cycle, that are greater than the target lineheight, the target linewidth, and the target grating duty cycle, respectively;
anisotropically etching the grating layer to form grating lines having the selected initial lineheight, the initial linewidth, and the initial grating duty cycle;
and
using an isotropic wet etch solution to etch back the grating lines to the target lineheight, the target linewidth, and the target grating duty cycle.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

13/244,033Filed 23 Sep 2011 · us provisional application

Priority

23 Sep 2010

Granted

3 Aug 2021

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

G02B 6/124
Basic optical elements, e.g. light-guiding paths: geodesic lenses or integrated gratings
G02B 6/136
Integrated optical circuits characterised by the manufacturing method: by etching
G02B 6/13
Of the integrated circuit kind: integrated optical circuits characterised by the manufacturing method
H01S 3/0057
Optical devices external to the laser cavity, specially adapted for lasers, e.g. for homogenisation of the beam or for manipulating laser…

Isotropic etchback method of linewidth tailoring multilayer dielectric diffraction gratings for improvement of laser damage resistance and diffraction efficiency

Life of this patent

Isotropic etchback method of linewidth tailoring multilayer dielectric diffraction gratings for improvement of laser damage resistance and diffraction efficiency

Life of this patent

Abstract

Claims6