A lithography mask may include a substrate layer. The lithography mask may include a multilayer reflective film disposed on the substrate layer and forming a first pattern, wherein the multilayer reflective film is configured to receive incident light and reflect a portion of the incident light toward an imaging collection pupil. The lithography mask may include a grating forming a second pattern on the substrate layer and configured to receive the incident light and deflect an additional portion of the incident light outside of the imaging collection pupil. The lithography mask may be inspected by an Actinic Patterned Mask Inspection (APMI) system. The second pattern may include a reflective film deposited on the grating.

A method for detecting printing defects in a photolithography mask that will print on a wafer when using the photolithography mask in a specific photolithography system to print semiconductor structures on the wafer, the method comprising: acquiring a first aerial image of the photolithography mask using a mask inspection system; generating a second aerial image of the photolithography mask by applying a machine learning model (26) to the first aerial image, wherein the machine learning model is trained to map a first aerial image acquired by a mask inspection system to a second aerial image that emulates the application of the specific photolithography system to the photolithography mask; and detecting printing defects in the photolithography mask by comparing the second aerial image to a reference image.

The invention relates to a method for detecting defects in a photolithography mask, the method comprising: i. Acquiring an aerial image of the photolithography mask; ii. Obtaining an underlying design of the photolithography mask; iii. Generating a plausible design of the acquired aerial image by solving an optimization problem that minimizes the deviation of a simulated aerial image of the plausible design from the acquired aerial image; and iv. Detecting defects in the photolithography mask by comparing the underlying design to the plausible design. The invention also relates to a corresponding system for detecting defects.

Systems and methods are provided for adjusting a fluid dispenser for depositing drops of formable material. According to embodiments, a system obtains an image of a substrate including a film formed on the substrate by curing the formable material deposited by a first dispenser and a second dispenser. Intensity information is obtained for pixels of the image and a difference is determined between intensity values from a portion of the substrate on which the first dispenser deposited drops and intensity values from a portion on which the second dispenser deposited drops, the intensity values corresponding to a region of the substrate associated with a target thickness. Adjustments based on the intensity values are made to change a drop volume and a drop density for nozzles of the first dispenser and nozzles of the second dispenser.

According to one aspect of the present invention, a pattern inspection apparatus includes: an imaging sensor including a plurality of first detection elements that detect light flux transmitted through or reflected by a target object illuminated with inspection Light and capture a pattern image of the target object, and a plurality of second detection elements that are arranged adjacent to the plurality of first detection elements, detect Light fluxes obtained by shifting a focus position of the light flux front side and rear side, and capture images for focus adjustment; an adjustment mechanism configured to adjust a focal position of the light flux by using the images for the focus adjustment captured by the plurality of second detection elements; and a comparison circuit configured to compare the pattern image captured by the plurality of first detection elements and a predetermined reference image.

A method of determining a relationship between a stochastic variation of a characteristic of an aerial image or a resist image and one or more design variables, the method including: measuring values of the characteristic from a plurality of aerial images and/or resist images for each of a plurality of sets of values of the design variables; determining a value of the stochastic variation, for each of the plurality of sets of values of the design variables, from a distribution of the values of the characteristic for that set of values of the design variables; and determining the relationship by fitting one or more parameters from the values of the stochastic variation and the plurality of sets of values of the design variables.

The present disclosure relates to a method of processing a phase-shift mask for EUV lithography, comprising: particle beam-induced depositing of a repair material using a precursor gas for repair of an imaging structure of the mask. According to the disclosure, the imaging structure can be repaired in such a way that at least one critical dimension of the mask has a deviation from a predetermined critical dimension of at least below 15%, preferably below 10%, more preferably below 5%, most preferably below 3%.

The present disclosure further relates to a phase-shift mask for EUV lithography, to a computer program and to a device.

A method of inspecting a risk of printing defective pattern in photolithography process, including generating an intensity curve of a photomask pattern in aerial image simulation, wherein the intensity curve is provided with a primary trough and a secondary troughs adjacent to the primary trough, the aerial image simulation is provided with a threshold intensity intersecting one of the secondary troughs to define an intensity region, partitioning the intensity region into multiple rectangular fragments, summing up areas of the rectangular fragments to obtain a total area, and determining the photomask pattern having no risk of forming defective pattern if the total area is smaller than a spec value and determining the photomask pattern having risk of forming defective pattern if the total area is larger than the spec value.

A metrology system includes an imaging system. The imaging system may include an objective lens. The metrology system may include one or more detectors. The metrology system may include an objective positioning stage structurally coupled to the objective lens and configured to adjust a focal plane of at least one of the one or more detectors via movement along an optical axis of the metrology system. The metrology system may include one or more proximity sensors configured to measure lateral positions of a stage element as the objective positioning stage moves along the optical axis. The metrology system may be configured to determine a metrology measurement associated with a target on a sample using the images and lateral positions of the stage element when implementing a metrology recipe.

A method for improving imaging of a feature on a mask to a substrate during scanning operation of a lithographic apparatus. The method includes obtaining a dynamic pupil representing evolution of an angular distribution of radiation exposing a mask during a scanning operation of a lithographic apparatus and determining a variation of shift of a feature at a substrate during the scanning operation due to interaction of the dynamic pupil with the mask. The method includes configuring a mask parameter and/or or a control parameter of the lithographic apparatus to reduce the variation of shift of the feature.