System and method for image segmentation from sparse particle impingement data

A system for segmenting a plurality of features of a substrate from sparse imaging data, the substrate comprising a plurality of features, the system comprising:

• a digital application operable to receive as input sparse imaging data related to an intensity value, as measured by a particle sensor, associated with post-impingement particles resulting from impingement of a substrate surface with a particle beam at each of a plurality of sensing locations, and at least one other particle sensor different from the particle sensor, said plurality of sensing locations defining a subset of locations within an area of interest of the substrate, said digital application further operable to:
• calculate, for each sensing location, a measured intensity based on the intensity value of the plurality of sensing locations;
• calculate, for each of a plurality of estimated locations defining a further subset of said area of interest, a corresponding estimated intensity based on a noise property of said one or more proximal measured intensities and at least one of the following corresponding to one or more locations proximal to each of the plurality of estimated locations:
• one or more proximal measured intensities, and one or more proximal estimated intensities, wherein said noise property for each proximal measured intensity is determined based on a difference between noise measured by said particle sensor and said at least one other particle sensor at the sensing location corresponding thereto;
• and
• segment each of said plurality of estimated locations, based on said corresponding estimated intensity, and each of said plurality of sensing locations, based on a corresponding measured intensity, to correspond to one of the plurality of features.