Abstract: A detector is provided for forming images by detecting electrons in an electron microscope at energies in the range of 3 keV to 300 keV, more specifically in the range of 40 keV to 120 keV with very high spatial resolution and sensitivity. The detector is formed by bonding a handling wafer to the front side of a planarized monolithic active pixel sensor (MAPS), partially or completely removing the substrate layer on the back side and selectively removing the handling material from the front side to leave a periphery of handling material in the non-image forming area. The detector may be mounted in an electron microscope for back side illumination. The detector provides high resolution images at low-energies due to back side illumination and at higher energies due to a decreased epitaxial layer thickness and the absence of any backscattering substrate material.

Abstract: A method of, and a detector for, performing energy sensitive imaging of ionizing radiation are provided, including acquiring a first frame having a plurality of pixels, each pixel of the plurality having an energy of detection and a location; grouping, into a cluster, pixels of the plurality having an energy of detection above a predetermined threshold and a location along with at least one other pixel also having an energy of detection above the predetermined threshold and being within a predetermined distance of the location; summing the energy of detection of all pixels within the grouped cluster to determine a cluster energy; determining a location of the cluster based on a distribution and an intensity of the summed energy of detection; and generating an image of the cluster based on the determined cluster energy and the determined location of the cluster.

Abstract: The present disclosure relates to transmission electron microscopy for evaluation of biological matter. According to an embodiment, the present disclosure further relates to an apparatus for determining the structure and/or elemental composition of a sample using 4D STEM, comprising a direct bombardment detector operating with global shutter readout, processing circuitry configured to acquire images of bright-field disks using either a contiguous array or non-contiguous array of detector pixel elements, correct distortions in the images, align each image of the images based on a centroid of the bright-field disk, calculate a radial profile of the images, normalize the radial profiles by a scaling factor, calculate the rotationally-averaged edge profile of the bright-field disk, and determine elemental composition within the specimen based on the characteristics of the edge profile of the bright-field disk corresponding to each specimen location.

Abstract: The present disclosure relates to an apparatus and methods for generating a hybrid image by high-dynamic-range counting. In an embodiment, the apparatus includes a processing circuitry configured to acquire an image from a pixelated detector, obtain a sparsity map of the acquired image, the sparsity map indicating low-flux regions of the acquired image and high-flux regions of the acquired image, generate a low-flux image and a high-flux image based on the sparsity map, perform event analysis of the acquired image based on the low-flux image and the high-flux image, the event analysis including detecting, within the low-flux image, incident events by an event counting mode, multiply, by a normalization constant, resulting intensities of the high-flux image and the detected incident events of the low-flux image, and generate the hybrid image by merging the low-flux image and the high-flux image.

Abstract: The present disclosure relates to transmission electron microscopy for evaluation of biological matter. According to an embodiment, the present disclosure further relates to an apparatus for determining the structure and/or elemental composition of a sample using 4D STEM, comprising a direct bombardment detector operating with global shutter readout, processing circuitry configured to acquire images of bright-field disks using either a contiguous array or non-contiguous array of detector pixel elements, correct distortions in the images, align each image of the images based on a centroid of the bright-field disk, calculate a radial profile of the images, normalize the radial profiles by a scaling factor, calculate the rotationally-averaged edge profile of the bright-field disk, and determine elemental composition within the specimen based on the characteristics of the edge profile of the bright-field disk corresponding to each specimen location.

Abstract: The present disclosure relates to an apparatus and methods for generating a hybrid image by high-dynamic-range counting. In an embodiment, the apparatus includes a processing circuitry configured to acquire an image from a pixelated detector, obtain a sparsity map of the acquired image, the sparsity map indicating low-flux regions of the acquired image and high-flux regions of the acquired image, generate a low-flux image and a high-flux image based on the sparsity map, perform event analysis of the acquired image based on the low-flux image and the high-flux image, the event analysis including detecting, within the low-flux image, incident events by an event counting mode, multiply, by a normalization constant, resulting intensities of the high-flux image and the detected incident events of the low-flux image, and generate the hybrid image by merging the low-flux image and the high-flux image.

Abstract: A method of imaging of a specimen exposed to an electron beam signal includes acquiring an image sequence of sequential images of the specimen. Each subsequent image in the image sequence represents increased cumulative electron beam signal exposure on the specimen. The method includes collecting cumulative exposure data for each image of the image sequence. The method includes applying a low-pass image processing filter to the images of the image sequence using the cumulative exposure data corresponding to each image to which the filter is being applied to produce processed images. The method includes combining the processed images to produce a final image. A method of imaging is also provided that includes selectively discarding images in the image sequence.

Abstract: A method of high-energy particle imaging by individual particle counting with an active pixel direct bombardment detector. The method includes the step of providing an active pixel direct bombardment detector including an array of pixels. Each pixel is characterized by a reset time constant. The method further includes sampling the pixel voltage of each pixel at a first time. The method further includes applying a pixel reset voltage to each pixel for a reset time interval less than the reset time constant. The method further includes sampling the pixel voltage of each pixel at a second time. The method further includes computing a difference between the sampled pixel voltages at the first and second times. The sampling and the applying of the reset voltage may be periodic. A direct bombardment detector is also provided.