# US 2024/0201426 A1 · Multi-layer high-efficiency dielectric grating with improved manufacturability > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0201426 A1 - Document ID: US20240201426A1 - Status: Published application - Kind: A1 - Application number: 18/382,366 - Filed: 2023-10-20 - Published: 2024-06-20 - Earliest claimed: 2022-12-14 - Assignees: II-Vi Delaware, Inc. - Applicants: II-VI Delaware, Inc. - Inventors: Justin Hannigan; Dmitri Iazikov; Christoph Greiner; John Hostetler - Web page: https://patentgrep.com/patent/US20240201426A1 ## CPC - G02B 5/1857: {using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams} - G02B 5/1861: {Reflection gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials (G02B5/1809, G02B5/1828, G02B5/1833, G02B5/1838 and G02B5/1847 take precedence)} - G02B 5/1866: {Transmission gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials (G02B5/1809, G02B5/1828, G02B5/1833, G02B5/1838 and G02B5/1847 take precedence)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract Systems and methods are provided for multi-layer high-efficiency dielectric grating with improved manufacturability. An example diffraction grating based morphology includes a plurality of grating lines; a plurality of intermediate layers; and a substrate bearing both of the plurality of grating lines and the plurality of intermediate layers; where one or more of the plurality of grating lines include a plurality of grating layers; and where at least two of the plurality of grating layers include different refractive index (RI) material. The plurality of grating layers includes one or more layers having low refractive index (RI) material and one or more layers having high refractive index (RI) material. The plurality of intermediate layers includes a plurality of matching layers and a plurality of dielectric layers. ## Claims ### Claim 1 A diffraction grating based morphology comprising: a plurality of grating lines; a plurality of intermediate layers; and a substrate bearing both of the plurality of grating lines and the plurality of intermediate layers; wherein one or more of the plurality of grating lines comprise a plurality of grating layers; and wherein at least two of the plurality of grating layers comprise different refractive index (RI) material. ### Claim 2 (depends on 1) The diffraction grating based morphology according to claim 1, wherein the plurality of grating layers comprises one or more layers comprising low refractive index (RI) material and one or more layers comprising high refractive index (RI) material. ### Claim 3 (depends on 2) The diffraction grating based morphology according to claim 2, wherein a top layer of the plurality of grating layers comprises low refractive index (RI) material. ### Claim 4 (depends on 2) The diffraction grating based morphology according to claim 2, wherein the one or more layers comprising low refractive index (RI) material and one or more layers comprising high refractive index (RI) material are arranged in alternating manner. ### Claim 5 (depends on 2) The diffraction grating based morphology according to claim 2, wherein the low refractive index (RI) material comprises silicon dioxide (SiO2). ### Claim 6 (depends on 2) The diffraction grating based morphology according to claim 2, wherein the high refractive index (RI) material comprises hafnium dioxide (HfO2). ### Claim 7 (depends on 1) The diffraction grating based morphology according to claim 1, wherein the plurality of intermediate layers comprises a plurality of matching layers. ### Claim 8 (depends on 7) The diffraction grating based morphology according to claim 7, wherein a first layer of the plurality of matching layers that is in contact with the plurality of grating lines is an etch-stop layer. ### Claim 9 (depends on 8) The diffraction grating based morphology according to claim 8, wherein the etch-stop layer comprises high refractive index (RI) material. ### Claim 10 (depends on 7) The diffraction grating based morphology according to claim 7, wherein the plurality of matching layers comprises layers having different refractive index (RI) material. ### Claim 11 (depends on 10) The diffraction grating based morphology according to claim 10, wherein the plurality of matching layers comprises one or more layers comprising low refractive index (RI) material and one or more layers comprising high refractive index (RI) material. ### Claim 12 (depends on 11) The diffraction grating based morphology according to claim 11, wherein the one or more layers comprising low refractive index (RI) material and one or more layers comprising high refractive index (RI) material are arranged in alternating manner. ### Claim 13 (depends on 11) The diffraction grating based morphology according to claim 11, wherein the low refractive index (RI) material comprises silicon dioxide (SiO2). ### Claim 14 (depends on 11) The diffraction grating based morphology according to claim 11, wherein the high refractive index (RI) material comprises hafnium dioxide (HfO2). ### Claim 15 (depends on 1) The diffraction grating based morphology according to claim 1, wherein the plurality of intermediate layers comprises a plurality of dielectric layers. ### Claim 16 (depends on 15) The diffraction grating based morphology according to claim 15, wherein the plurality of dielectric layers comprises layers having different refractive index (RI) material. ### Claim 17 (depends on 16) The diffraction grating based morphology according to claim 16, wherein the plurality of dielectric layers comprises one or more layers comprising low refractive index (RI) material and one or more layers comprising high refractive index (RI) material. ### Claim 18 (depends on 17) The diffraction grating based morphology according to claim 17, wherein the one or more layers comprising low refractive index (RI) material and one or more layers comprising high refractive index (RI) material are arranged in alternating manner. ### Claim 19 (depends on 17) The diffraction grating based morphology according to claim 17, wherein the low refractive index (RI) material comprises silicon dioxide (SiO2). ### Claim 20 (depends on 17) The diffraction grating based morphology according to claim 17, wherein the one or more layers comprising high refractive index (RI) material comprises at least one first layer comprising a first high refractive index (RI) material and at least one second layer comprising a second high refractive index (RI) material, and wherein the first high refractive index (RI) material and the second high refractive index (RI) material are different. ### Claim 21 (depends on 20) The diffraction grating based morphology according to claim 20, wherein the first high refractive index (RI) material comprises tantalum pentoxide (Ta2O5). ### Claim 22 (depends on 20) The diffraction grating based morphology according to claim 20, wherein the second high refractive index (RI) material comprises hafnium dioxide (HfO2). ### Claim 23 (depends on 1) The diffraction grating based morphology according to claim 1, wherein the substrate comprises silicon (Si).