Disclosed is a method of, and associated apparatus for, determining an edge position relating to an edge of a feature comprised within an image, such as a scanning electron microscope image, which comprises noise. The method comprises determining a reference signal from said image; and determining said edge position with respect to said reference signal. The reference signal may be determined from the image by applying a 1-dimensional low-pass filter to the image in a direction parallel to an initial contour estimating the edge position.

A manufacturing method of a contact structure includes the following steps. A substrate is provided, and the substrate includes a first region and a second region. A dielectric layer is formed on the substrate. A photoresist layer is formed on the dielectric layer. An exposure process is performed. The exposure process includes first exposure steps and second exposure steps. Each of the first exposure steps is performed to a part of the first region of the substrate. Each of the second exposure steps is performed to a part of the second region of the substrate. Each of the second exposure steps is performed with a first overlay shift by a first predetermined distance. A develop process is performed for forming openings in the photoresist layer.

A manufacturing method of a contact structure includes the following steps. A substrate is provided, and the substrate includes a first region and a second region. A dielectric layer is formed on the substrate. A photoresist layer is formed on the dielectric layer. An exposure process is performed. The exposure process includes first exposure steps and second exposure steps. Each of the first exposure steps is performed to a part of the first region of the substrate. Each of the second exposure steps is performed to a part of the second region of the substrate. Each of the second exposure steps is performed with a first overlay shift by a first predetermined distance. A develop process is performed for forming openings in the photoresist layer.

Disclosed is an object table for holding an object, comprising: an electrostatic clamp arranged to clamp the object on the object table; a neutralizer arranged to neutralize a residual charge of the electrostatic clamp; a control unit arranged to control the neutralizer, wherein the residual charge is an electrostatic charge present on the electrostatic clamp when no voltage is applied to the electrostatic clamp.

A method of detecting defects of a photoresist pattern includes generating a scanning electron microscope (SEM) image of a surface of a photoresist pattern and signal intensity data relative to pixel position of the surface of the photoresist pattern. The method also includes setting a lower reference intensity threshold value and an upper reference intensity threshold value used as reference values for detecting defects. The method further includes classifying a pixel position of the signal intensity data having a signal intensity value which is less than the lower reference intensity threshold value or greater than the upper reference intensity threshold value as a defect position.

A method of detecting defects of a photoresist pattern includes generating a scanning electron microscope (SEM) image of a surface of a photoresist pattern and signal intensity data relative to pixel position of the surface of the photoresist pattern. The method also includes setting a lower reference intensity threshold value and an upper reference intensity threshold value used as reference values for detecting defects. The method further includes classifying a pixel position of the signal intensity data having a signal intensity value which is less than the lower reference intensity threshold value or greater than the upper reference intensity threshold value as a defect position.

An optical system used in a charged particle beam inspection system. The optical system includes one or more optical lenses, and a compensation lens configured to compensate a drift of a focal length of a combination of the one or more optical lenses from a first medium to a second medium.

Systems and methods for optimal electron beam metrology guidance are disclosed. According to certain embodiments, the method may include receiving an acquired image of a sample, determining a set of image parameters based on an analysis of the acquired image, determining a set of model parameters based on the set of image parameters, generating a set of simulated images based on the set of model parameters. The method may further comprise performing measurement of critical dimensions on the set of simulated images and comparing critical dimension measurements with the set of model parameters to provide a set of guidance parameters based on comparison of information from the set of simulated images and the set of model parameters. The method may further comprise receiving auxiliary information associated with target parameters including critical dimension uniformity.

Systems and methods for optimal electron beam metrology guidance are disclosed. According to certain embodiments, the method may include receiving an acquired image of a sample, determining a set of image parameters based on an analysis of the acquired image, determining a set of model parameters based on the set of image parameters, generating a set of simulated images based on the set of model parameters. The method may further comprise performing measurement of critical dimensions on the set of simulated images and comparing critical dimension measurements with the set of model parameters to provide a set of guidance parameters based on comparison of information from the set of simulated images and the set of model parameters. The method may further comprise receiving auxiliary information associated with target parameters including critical dimension uniformity.

The present invention relates to a method for determining an alignment of a photomask on a sample stage which is displaceable along at least one axis that is parallel to a chuck surface of the sample stage, and is rotatable about at least one axis that is perpendicular to the chuck surface, which method comprises the following step:

rotating the sample stage by a predefined angle and measuring a height change of the photomask during rotation at a predetermined, non-vanishing distance with respect to the rotation axis for the purpose of determining the alignment of the photomask on the sample stage.