【NL2022732A】水平传感器和光刻设备【专利】

© 2022732
© Α OCTROOIAANVRAAG
(2?) Aanvraagnummer: 2022732© Int. Cl.:
G03F 7/20 (2019.01)
© Aanvraag ingediend: 13 maart 2019
© Voorrang:
11 april 2018 EP 18166754.4© Aanvrager(s):ASML Netherlands B.V. te Veldhoven.© Aanvraag ingeschreven:
16 oktober 2019
(43) Aanvraag gepubliceerd:
16 oktober 2019© Uitvinder(s):Simon Reinald Huisman te Veldhoven.Marinus Petrus Reijnders te Veldhoven.
© Gemachtigde:
Ir. A.J. Maas te Veldhoven.
(54) LEVEL SENSOR AND LITHOGRAPHIC APPARATUS
(57) The invention provides a level sensor to measure a position of a surface of a substrate, comprising a projection
unit arranged to direct a beam of radiation to the surface of the substrate and a detection unit. The detection unit comprises a detection grating arranged to receive the beam of radiation reflected on the surface of the substrate, one or more detectors, one or more optical elements to direct the beam of radiation from the detection grating to the one or more detectors, and a processing unit to determine the position of the surface of the substrate on the basis of the beam of radiation received by the one or more detectors. The detection grating and the one or more optical elements are integrated in a single integrated optical element.
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stukken.
LEVEL SENSOR AND LITHOGRAPHIC APPARATUS
5 10 15 20 25 30FIELD
[0001]The present invention relates to a level sensor and a lithographic apparatus comprising such level sensor.
BACKGROUND
[0002]A lithographic apparatus is a machine constructed to apply a desired pattern onto a substrate.A lithographic apparatus can be used,for example,in the manufacture of integrated circuits(ICs).A lithographic apparatus may,for example,project a pattern(also often referred to as“design layout”or“design”)of a patterning device(e.g.,a mask)onto a layer of radiation­sensitive material(resist)provided on a substrate(e.g.,a wafer).
[0003]As semiconductor manufacturing processes continue to advance,the dimensions of circuit elements have continually been reduced while the amount of functional elements,such as transistors,per device has been steadily increasing over decades,following a trend commonly referred to as‘Moore's law’.To keep up with Moore’s law the semiconductor industry is chasing technologies that enable to create increasingly smaller features.To project a pattern on a substrate a lithographic apparatus may use electromagnetic radiation.The wavelength of this radiation determines the minimum size of features which are patterned on the substrate.Typical wavelengths currently in use are365nm(i-line),248nm,193nm and13.5nm.A lithographic apparatus,which uses extreme ultraviolet(EUV)radiation,having a wavelength within a range of4nm to20nm,for example6.7nm or13.5nm,may be used to form smaller features on a substrate than a lithographic apparatus which uses,for example,radiation with a wavelength of 193nm.
[0004]A topography measurement system,level sensor or height sensor,and which may be integrated in the lithographic apparatus,is arranged to measure a topography of a top surface of a substrate(or wafer).A map of the topography of the substrate,also referred to as height map, may be generated from these measurements indicating a height of the substrate as a function of the position on the substrate.This height map may subsequently be used to correct the position of the substrate during transfer of the pattern on the substrate,in order to provide an aerial image of the patterning device in a properly focus position on the substrate.It will be understood that。