Abstract: A method for process control of a semiconductor structure fabricated by a series of fabrication steps, the method comprising obtaining an image of the semiconductor structure indicative of at least two individual fabrication steps; wherein the image is generated by scanning the semiconductor structure with a charged particle beam and collecting signals emanating from the semiconductor structure; and processing, by a hardware processor, the image to determining a parameter of the semiconductor structure, wherein processing includes measuring step/s from among the fabrication steps as an individual feature.

Abstract: An improved technique for determining height difference in patterns provided on semiconductor wafers uses real measurements (e.g., measurements from SEM images) and a height difference determination model. In one version of the model, a measurable variable of the model is expressed in terms of a function of a change in depth of shadow (i.e. relative brightness), wherein the depth of shadow depends on the height difference as well as width difference between two features on a semiconductor wafer. In another version of the model, the measurable variable is expressed in terms of a function of a change of a measured distance between two characteristic points on the real image of a periodic structure with respect to a change in a tilt angle of a scanning electron beam.

Abstract: A method for process control of a semiconductor structure fabricated by a series of fabrication steps, the method comprising obtaining an image of the semiconductor structure indicative of at least two individual fabrication steps; wherein the image is generated by scanning the semiconductor structure with a charged particle beam and collecting signals emanating from the semiconductor structure; and processing, by a hardware processor, the image to determining a parameter of the semiconductor structure, wherein processing includes measuring step/s from among the fabrication steps as an individual feature.

Abstract: An improved technique for determining height difference in patterns provided on semiconductor wafers uses real measurements (e.g., measurements from SEM images) and a height difference determination model. In one version of the model, a measurable variable of the model is expressed in terms of a function of a change in depth of shadow (i.e. relative brightness), wherein the depth of shadow depends on the height difference as well as width difference between two features on a semiconductor wafer. In another version of the model, the measurable variable is expressed in terms of a function of a change of a measured distance between two characteristic points on the real image of a periodic structure with respect to a change in a tilt angle of a scanning electron beam.

Abstract: An improved technique for determining height difference in patterns provided on semiconductor wafers uses real measurements (e.g., measurements from SEM images) and a height difference determination model. In one version of the model, a measurable variable of the model is expressed in terms of a function of a change in depth of shadow (i.e. relative brightness), wherein the depth of shadow depends on the height difference as well as width difference between two features on a semiconductor wafer. In another version of the model, the measurable variable is expressed in terms of a function of a change of a measured distance between two characteristic points on the real image of a periodic structure with respect to a change in a tilt angle of a scanning electron beam.

Abstract: A method for monitoring a first nanometric structure formed by a multiple patterning process, the method may include performing a first plurality of measurements to provide a first plurality of measurement results; wherein the performing of the first plurality of measurements comprises illuminating first plurality of locations of a first sidewall of the first nanometric structure by oblique charged particle beams of different tilt angles; and processing, by a hardware processor, the first plurality of measurement results to determine a first attribute of the first nanometric structure.

Abstract: A method for monitoring a first nanometric structure formed by a multiple patterning process, the method may include performing a first plurality of measurements to provide a first plurality of measurement results; wherein the performing of the first plurality of measurements comprises illuminating first plurality of locations of a first sidewall of the first nanometric structure by oblique charged particle beams of different tilt angles; and processing, by a hardware processor, the first plurality of measurement results to determine a first attribute of the first nanometric structure.

Abstract: A method for determining overlay between layers of a multilayer structure may include obtaining a given image representing the multilayer structure, obtaining expected images for layers of the multilayer structure, providing a combined expected image of the multilayer structure as a combination of the expected images of said layers, performing registration of the given image against the combined expected image, and providing segmentation of the given image, thereby producing a segmented image, and maps of the layers of said multilayered structure. The method may further include determining overlay between any two selected layers of the multilayer structure by processing the maps of the two selected layers together with the expected images of said two selected layers.

Abstract: An improved technique for determining height difference in patterns provided on semiconductor wafers uses real measurements (e.g., measurements from SEM images) and a height difference determination model. In one version of the model, a measurable variable of the model is expressed in terms of a function of a change in depth of shadow (i.e. relative brightness), wherein the depth of shadow depends on the height difference as well as width difference between two features on a semiconductor wafer. In another version of the model, the measurable variable is expressed in terms of a function of a change of a measured distance between two characteristic points on the real image of a periodic structure with respect to a change in a tilt angle of a scanning electron beam.

Abstract: A method for determining overlay between layers of a multilayer structure may include obtaining a given image representing the multilayer structure, obtaining expected images for layers of the multilayer structure, providing a combined expected image of the multilayer structure as a combination of the expected images of said layers, performing registration of the given image against the combined expected image, and providing segmentation of the given image, thereby producing a segmented image, and maps of the layers of said multilayered structure. The method may further include determining overlay between any two selected layers of the multilayer structure by processing the maps of the two selected layers together with the expected images of said two selected layers.

Abstract: A method for determining overlay between layers of a multilayer structure may include obtaining a given image representing the multilayer structure, obtaining expected images for layers of the multilayer structure, providing a combined expected image of the multilayer structure as a combination of the expected images of said layers, performing registration of the given image against the combined expected image, and providing segmentation of the given image, thereby producing a segmented image, and maps of the layers of said multilayered structure. The method may further include determining overlay between any two selected layers of the multilayer structure by processing the maps of the two selected layers together with the expected images of said two selected layers.

Abstract: A method for determining overlay between layers of a multilayer structure may include obtaining a given image representing the multilayer structure, obtaining expected images for layers of the multilayer structure, providing a combined expected image of the multilayer structure as a combination of the expected images of said layers, performing registration of the given image against the combined expected image, and providing segmentation of the given image, thereby producing a segmented image, and maps of the layers of said multilayered structure. The method may further include determining overlay between any two selected layers of the multilayer structure by processing the maps of the two selected layers together with the expected images of said two selected layers.

Abstract: A method for determining overlay between layers of a multilayer structure may include obtaining a given image representing the multilayer structure, obtaining expected images for layers of the multilayer structure, providing a combined expected image of the multilayer structure as a combination of the expected images of said layers, performing registration of the given image against the combined expected image, and providing segmentation of the given image, thereby producing a segmented image, and maps of the layers of said multilayered structure. The method may further include determining overlay between any two selected layers of the multilayer structure by processing the maps of the two selected layers together with the expected images of said two selected layers.

Abstract: A method for determining overlay between layers of a multilayer structure may include obtaining a given image representing the multilayer structure, obtaining expected images for layers of the multilayer structure, providing a combined expected image of the multilayer structure as a combination of the expected images of said layers, performing registration of the given image against the combined expected image, and providing segmentation of the given image, thereby producing a segmented image, and maps of the layers of said multilayered structure. The method may further include determining overlay between any two selected layers of the multilayer structure by processing the maps of the two selected layers together with the expected images of said two selected layers.

Abstract: A system, a non-transitory computer readable medium and a method for detecting a parameter of a pattern, the method comprises: obtaining an image of the pattern; wherein the image is generated by scanning the pattern with a charged particle beam; processing the image to provide an edge enhanced image; wherein the processing comprises computing an aggregate energy of first n spectral components of the image, wherein n exceeds two; and further processing the edge enhanced image and determining a parameter of the pattern.

Abstract: A method for characterizing a surface of a sample object, the method including dividing the surface into pixels which are characterized by a parameter variation, and defining blocks of the surface as respective groups of the pixels. The method further includes irradiating the pixels in multiple scans over the surface with radiation having different, respective types of polarization, and detecting returning radiation from the pixels in response to each of the scans. For each scan, respective block signatures of the blocks are constructed, in response to the returning radiation from the group of pixels in each block. Also for each scan, a block signature variation using the respective block signatures of the blocks is determined. In response to the block signature variation, one or more of the types of polarization for use in subsequent examination of a test object are selected.

Abstract: A method for characterizing a surface of a sample object, the method including dividing the surface into pixels which are characterized by a parameter variation, and defining blocks of the surface as respective groups of the pixels. The method further includes irradiating the pixels in multiple scans over the surface with radiation having different, respective types of polarization, and detecting returning radiation from the pixels in response to each of the scans. For each scan, respective block signatures of the blocks are constructed, in response to the returning radiation from the group of pixels in each block. Also for each scan, a block signature variation using the respective block signatures of the blocks is determined. In response to the block signature variation, one or more of the types of polarization for use in subsequent examination of a test object are selected.

Abstract: In its preferred embodiment, the sinuous toy is a mechanical snake with a plurality of body elements. The body elements are each pivoted with respect to each adjacent body element on a vertical axis. Each body element has a large circular opening therethrough. The body elements are configured to be more narrow laterally away from the pivot axis so that the body elements can swing with respect to each other to represent sinuous snake motion. A helical actuator coil extends through the interior opening of the plurality of body elements. The outside swept diameter of the helical coil actuator is slightly larger than the interior openings through the body elements so that the body elements rise and fall in a direction generally parallel to the pivot axes between the body elements. Means is provided to supply tension between the head and tail of the sinuous toy so that the body elements are thrust sideways to have twice as much sideways motion as the interior diameter of the body elements.