摘要:
A scatterometer, configured to measure a property of a substrate, includes a radiation source which produces a radiation spot on a target formed on the surface of the substrate, the size of the radiation spot being smaller than the target in one direction along the target, the position of the radiation spot being moved along the surface in a series of discrete steps. A detector detects a spectrum of the radiation beam reflected from the target and produces measurement signals representative of the spectrum corresponding to each position of the radiation spot. A processor processes the measurement signals produced by the detector corresponding to each position of the radiation spot and derives a single value for the property.
摘要:
An apparatus and method to determine a property of a substrate by measuring, in the pupil plane of a high numerical aperture lens, an angle-resolved spectrum as a result of radiation being reflected off the substrate. The property may be angle and wavelength dependent and may include the intensity of TM- and TE-polarized radiation and their relative phase difference.
摘要:
A scatterometer has a focus sensor arranged to detect whether the target being measured is in a correct focal plane. A modulation is applied to a component of the focus sensor or the scatterometer such that a defocus as measured by the focus sensor varies according to a certain function. From knowledge of the modulation, the gain of the sensor can be calibrated.
摘要:
A method of assessing a model of a substrate is presented. A scatterometry measurement is taken using radiation at a first wavelength. The wavelength of the radiation is then changed and a further scatterometry measurement taken. If the scatterometry measurements are consistent across a range of wavelengths then the model is sufficiently accurate. However, if the scatterometry measurements change as the wavelength changes then the model of the substrate is not sufficiently accurate.
摘要:
An apparatus and method to determine a property of a substrate by measuring, in the pupil plane of a high numerical aperture lens, an angle-resolved spectrum as a result of radiation being reflected off the substrate. The property may be angle and wavelength dependent and may include the intensity of TM- and TE-polarized radiation and their relative phase difference.
摘要:
A lithographic apparatus according to one embodiment of the invention includes an alignment subsystem configured to align the substrate on the substrate table relative to the patterning structure. The alignment structure comprises a non-periodic feature which may be detectable as e.g. a capture position or a check position using a reference grating in the alignment subsystem. The non-periodic feature may cause a phase effect in the detected signal of the alignment subsystem or an amplitude effect.
摘要:
For angular resolved spectrometry a radiation beam is used having an illumination profile having four quadrants is used. The first and third quadrants are illuminated whereas the second and fourth quadrants aren't illuminated. The resulting pupil plane is thus also divided into four quadrants with only the zeroth order diffraction pattern appearing in the first and third quadrants and only the first order diffraction pattern appearing in the second and third quadrants.
摘要:
A scatterometer, configured to measure a property of a substrate, includes a radiation source which produces a radiation spot on a target formed on the surface of the substrate, the size of the radiation spot being smaller than the target in one direction along the target, the position of the radiation spot being moved along the surface in a series of discrete steps. A detector detects a spectrum of the radiation beam reflected from the target and produces measurement signals representative of the spectrum corresponding to each position of the radiation spot. A processor processes the measurement signals produced by the detector corresponding to each position of the radiation spot and derives a single value for the property.
摘要:
An apparatus and method to determine a property of a substrate by measuring, in the pupil plane of a high numerical aperture lens, an angle-resolved spectrum as a result of radiation being reflected off the substrate. The property may be angle and wavelength dependent and may include the intensity of TM- and TE-polarized radiation and their relative phase difference.
摘要:
For angular resolved spectrometry a radiation beam is used having an illumination profile having four quadrants is used. The first and third quadrants are illuminated whereas the second and fourth quadrants aren't illuminated. The resulting pupil plane is thus also divided into four quadrants with only the zeroth order diffraction pattern appearing in the first and third quadrants and only the first order diffraction pattern appearing in the second and third quadrants.