# US 2018/0024436 A1 · Active eye-to-eye with alignment by x-y capacitance measurement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0024436 A1 - Document ID: US20180024436A1 - Status: Published application - Kind: A1 - Application number: 15/629,183 - Filed: 2017-06-21 - Published: 2018-01-25 - Earliest claimed: 2016-07-22 - Assignees: Applied Materials, Inc. - Applicants: Applied Materials, Inc. - Inventors: Thomas L. LAIDIG; Jeffrey KASKEY - Web page: https://patentgrep.com/patent/US20180024436A1 ## CPC - G03F 7/7085: {Detection arrangement, e.g. detectors of apparatus alignment possibly mounted on wafers, exposure dose, photo-cleaning flux, stray light, thermal load} - G03F 7/2008: {characterised by the reflectors, diffusers, light or heat filtering means or anti-reflective means used} - G03F 7/201: {characterised by an oblique exposure; characterised by the use of plural sources; characterised by the rotation of the optical device; characterised by a relative movement of the optical device, the light source, the sensitive system or the mask} - G03F 7/2051: {Exposure without an original mask, e.g. using a programmed deflection of a point source, by scanning, by drawing with a light beam, using an addressed light or corpuscular source (G03F7/70 takes precedence)} - G03F 7/70258: {Projection system adjustments, e.g. adjustments during exposure or alignment during assembly of projection system} - G03F 7/70275: {Multiple projection paths, e.g. array of projection systems, microlens projection systems or tandem projection systems} - G03F 7/70833: {Mounting of optical systems, e.g. mounting of illumination system, projection system or stage systems on base-plate or ground} - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract Embodiments of the present disclosure generally relate to systems and methods for performing photolithography processes. In one embodiment, a photolithography system includes a plurality of image projection systems each having an extendable lens, and a plate having a plurality of openings. Each extendable lens is configured to be extended through a corresponding opening of the plurality of openings during operation. The plate includes one or more elements disposed adjacent each opening and each lens includes one or more elements formed thereon. The one or more elements formed on the plate and the one or more elements formed on the lens are utilized to measure one or more distances between the lens and the plate. Any deviation of the measured distance from a reference distance indicates that the lens has been shifted. Measures to compensate for the shifting of the lens will be performed. ## Claims ### Claim 1 A photolithography system, comprising: a slab; a chuck disposed on the slab; a plurality of image projection systems disposed over the slab, wherein each image projection system of the plurality of image projection systems includes a lens, wherein the lens includes a lens housing; one or more sensors coupled to the lens housing of the lens of each image projection system; and a plate disposed between the slab and the plurality of image projection systems, wherein the plate includes a plurality of openings and one or more targets disposed adjacent to each opening of the plurality of openings. ### Claim 2 (depends on 1) The photolithography system of claim 1, wherein the one or more sensors comprise one or more capacitance sensors. ### Claim 3 (depends on 2) The photolithography system of claim 2, wherein the one or more targets comprise one or more metal bars. ### Claim 4 (depends on 1) The photolithography system of claim 1, wherein the one or more sensors comprise a first sensor and a second sensor, and the one or more targets comprise a first target and a second target. ### Claim 5 (depends on 4) The photolithography system of claim 4, wherein the first sensor and the first target are aligned in a first direction, and the second sensor and the second target are aligned in a second direction. ### Claim 6 (depends on 4) The photolithography system of claim 4, wherein the one or more sensors further comprise a third sensor and a fourth sensor, and the one or more targets further comprise a third target and a fourth target. ### Claim 7 (depends on 6) The photolithography system of claim 6, wherein the third sensor and the third target are aligned in the first direction, and the fourth sensor and the fourth target are aligned in the second direction. ### Claim 8 (depends on 1) The photolithography system of claim 1, wherein the plate further comprises one or more interferometers. ### Claim 9 A photolithography system, comprising: a slab; a chuck disposed on the slab; a plurality of image projection systems disposed over the slab, wherein each image projection system of the plurality of image projection systems includes a lens, wherein the lens includes a lens housing; one or more targets coupled to the lens housing of the lens of each image projection system; and a plate disposed between the slab and the plurality of image projection systems, wherein the plate includes a plurality of openings and one or more sensors disposed adjacent to each opening of the plurality of openings. ### Claim 10 (depends on 9) The photolithography system of claim 9, wherein the one or more sensors comprise one or more capacitance sensors. ### Claim 11 (depends on 10) The photolithography system of claim 10, wherein the one or more targets comprise one or more metal bars. ### Claim 12 (depends on 9) The photolithography system of claim 9, wherein the one or more sensors comprise a first sensor and a second sensor, and the one or more targets comprise a first target and a second target. ### Claim 13 (depends on 12) The photolithography system of claim 12, wherein the first sensor and the first target are aligned in a first direction, and the second sensor and the second target are aligned in a second direction. ### Claim 14 (depends on 12) The photolithography system of claim 12, wherein the one or more sensors further comprise a third sensor and a fourth sensor, and the one or more targets further comprise a third target and a fourth target. ### Claim 15 (depends on 14) The photolithography system of claim 14, wherein the third sensor and the third target are aligned in the first direction, and the fourth sensor and the fourth target are aligned in the second direction. ### Claim 16 (depends on 9) The photolithography system of claim 9, wherein the plate further comprises one or more interferometers. ### Claim 17 A method, comprising: moving a substrate under a plurality of image projection systems, wherein each image projection system of the plurality of image projection systems includes a lens; extending the lens towards the substrate disposed on a chuck, wherein the lens is extended through an opening formed in a plate, wherein the plate is disposed between the substrate and the plurality of image projection systems, wherein the plate includes one or more elements disposed adjacent to the opening; and measuring one or more distances between the lens and the one or more elements. ### Claim 18 (depends on 17) The method of claim 17, wherein the one or more elements comprise one or more sensors, wherein the lens includes a lens housing, and one or more targets are coupled to the lens housing. ### Claim 19 (depends on 17) The method of claim 17, wherein the one or more elements comprise one or more targets, wherein the lens includes a lens housing, and one or more sensors are coupled to the lens housing. ### Claim 20 (depends on 17) The method of claim 17, further comprising comparing the measured one or more distances to a reference distance.