摘要:
A lithographic apparatus includes an illuminator configured to condition a beam of radiation and a support configured to hold a patterning device. The patterning device is configured to pattern the beam of radiation according to a desired pattern. The lithographic apparatus also includes a substrate table configured to hold a substrate and a projection system configured to project the patterned beam onto a target portion of the substrate to form a patterned image on the substrate. The apparatus further includes a sensor configured and arranged to intercept a portion of the beam and to measure a transmission of the beam through at least a portion of the patterning device.
摘要:
System aberrations are effected in a projection system of a lithographic apparatus to optimize imaging of a thick reflective mask with a thick absorber that is obliquely illuminated. The aberrations may include Z5 astigmatism, Z9 spherical, and Z12 astigmatism.
摘要:
In a method according to one embodiment of the invention, aberrations in a lithographic apparatus are detected by printing a test pattern having at least one degree of symmetry and being sensitive to a particular aberration in the apparatus, and using a scatterometer to derive information concerning the aberration. The test structure may comprise a two-bar grating, in which case the inner and outer duty ratios can be reconstructed to derive information indicative of comatic aberration. Alternatively, a hexagonal array of dots can be used, such that scatterometry data can be used to reconstruct dot diameters indicative of 3-wave aberration.
摘要:
A method of device inspection, the method comprising providing an asymmetric marker on a device to be inspected, the form of asymmetry of the marker being dependent upon the parameter to be inspected, directing light at the marker, obtaining a first measurement of the position of the marker via detection of diffracted light of a particular wavelength or diffraction angle, obtaining a second measurement of the position of the marker via detection of diffracted light of a different wavelength or diffraction angle, and comparing the first and second measured positions to determine a shift indicative of the degree of asymmetry of the marker.
摘要:
A method according to an embodiment includes obtaining calibration measurement data, with an optical detection apparatus, from a plurality of marker structure sets provided on a calibration substrate. Each marker structure set includes at least one calibration marker structure created using different known values of the process parameter. The method includes obtaining measurement data, with the optical detection apparatus, from at least one marker structure provided on a substrate and exposed using an unknown value of the process parameter; and determining the unknown value of the process parameter from the obtained measurement data by employing regression coefficients in a model based on the known values of the process parameter and the calibration measurement data.
摘要:
In a method according to one embodiment of the invention, aberrations in a lithographic apparatus are detected by printing a test pattern having at least one degree of symmetry and being sensitive to a particular aberration in the apparatus, and using a scatterometer to derive information concerning the aberration. The test structure may comprise a two-bar grating, in which case the inner and outer duty ratios can be reconstructed to derive information indicative of comatic aberration. Alternatively, a hexagonal array of dots can be used, such that scatterometry data can be used to reconstruct dot diameters indicative of 3-wave aberration.
摘要:
A lithographic apparatus includes a radiation system having reflective optical elements constructed and arranged to condition a beam of radiation. The reflective optical elements include a first faceted mirror constructed and arranged to generate a plurality of source images on a second mirror. The lithographic apparatus also includes a facet mask constructed and arranged to selectively mask one or more of the facets of the first faceted mirror. The facet mask includes a masking blade selectively interposable into the beam.
摘要:
A lithographic apparatus includes a device having a blade selectively insertable into the beam. The device is in a first plane intermediate a second plane conjugate to a plane of the substrate and a third plane conjugate to a pupil plane of the projection system. The blade may include a partially opaque blade and a solid blade or have a predetermined transmissibility pattern. The transmissibility may vary in a second direction perpendicular to the first direction in which the substrate and the patterning device are movable. In an illumination system including a field faceted mirror and a pupil faceted mirror, a reflecting blade is selectively insertable into the beam to reflect a portion of the beam to a beam dump that may be cooled to reduce a heat load. The reflecting element may have a coating that scatters the portion of radiation or changes the phase.
摘要:
A lithographic projection apparatus includes a radiation system for providing a projection beam of radiation having a wavelength λ1 smaller than 50 nm; a support structure for supporting patterning structure, the patterning structure serving to pattern the projection beam according to a desired pattern; a substrate table for holding a substrate; and a projection system for projecting the patterned beam onto a target portion of the substrate. The apparatus further includes a radiation sensor which is located so as to be able to receive radiation out of the projection beam, said sensor comprising a radiation-sensitive material which converts incident radiation of wavelength λ1 into secondary radiation; and sensing means capable of detecting said secondary radiation emerging from said layer.
摘要:
A method of operating a lithographic projection apparatus including forming a spot of radiation at the wafer level using a pinhole at reticle level. A sensor is defocused with respect to the spot such that it is spaced apart from the wafer level. The sensor is scanned beneath the spot to measure the angular intensity distribution of radiation at the spot and to determine the intensity distribution at the pupil plane of the projection lens system.