Abstract: Implementations disclosed describe, among other things, a system and a method of using a wafer inspection system that includes a plurality of inspection heads configured to concurrently inspect a separate region of a plurality of regions of a wafer. Each inspection head includes an illumination subsystem to illuminate a corresponding region of the wafer, a collection subsystem to collect a portion of light reflected/scattered from the corresponding region of the wafer. Each inspection head further includes a light detection subsystem to detect the collected light and generate one or more signals representative of a state of the corresponding region of the wafer. The wafer inspection system further includes a processing device configured to determine, using the one or more signals received from each of the inspection heads, the quality of the wafer.

Abstract: A method and a light detector that includes (i) a photon to electron converter a photon to one or more photoelectrons; (ii) a photoelectron detection circuit that includes a photoelectron sensing region; (iii) a chamber; (iv) a bias circuit that is configured to supply to the light detector one or more biasing signals for accelerating a propagation of the one or more photoelectrons within the chamber and towards the photoelectron sensing region; (iv) a photoelectron manipulator that is configured to operate in a selected operational mode out of multiple operational modes that differ by their level of blocking, (v) a controller that is configured to control the photoelectron manipulator based on a feedback about the at least one of (a) the photon, (b) the one or more photoelectrons, (c) a previous photon and, (d) previous one or more photoelectrons.

Abstract: A detection module that includes a readout circuit and detector having a group of sensing elements. The group is configured to detect multiple beams. The multiple beams resulted from an illumination of a substrate, by an illumination module, by multiple electron beams. The readout circuit is configured to: (a) receive selection information for selecting multiple selected sub-groups of sensing elements; wherein the group of sensing elements comprises, in addition to the multiple selected sub-groups of sensing elements, a plurality of non-selected sensing elements; (b) ignore detection signals provided from the plurality of non-selected sensing elements, and (c) generate, for each selected sub-group of sensing elements, a sensing result to provide multiple sensing results that correspond to the multiple beams; and wherein the selected sub-groups of sensing elements are selected in response to at least one working condition of the illumination module.

Abstract: A detection module that includes a readout circuit and detector having a group of sensing elements. The group is configured to detect multiple beams. The multiple beams resulted from an illumination of a substrate, by an illumination module, by multiple electron beams. The readout circuit is configured to: (a) receive selection information for selecting multiple selected sub-groups of sensing elements; wherein the group of sensing elements comprises, in addition to the multiple selected sub-groups of sensing elements, a plurality of non-selected sensing elements; (b) ignore detection signals provided from the plurality of non-selected sensing elements, and (c) generate, for each selected sub-group of sensing elements, a sensing result to provide multiple sensing results that correspond to the multiple beams; and wherein the selected sub-groups of sensing elements are selected in response to at least one working condition of the illumination module.

Abstract: An optical module that includes (a) an optical interface that includes an input surface and an output surface, and (b) a scintillator that has a flat surface. The scintillator is configured emit emitted light through the flat surface in response to an impingement of a charged particle on the scintillator. The flat surface is optically coupled to the input surface. The optical interface is configured to (i) receive the emitted light from the scintillator and (ii) output, via the output surface, output light. An optical interface refractive index substantially equals a scintillator refractive index.

Abstract: An optical module that includes (a) an optical interface that includes an input surface and an output surface, and (b) a scintillator that has a flat surface. The scintillator is configured emit emitted light through the flat surface in response to an impingement of a charged particle on the scintillator. The flat surface is optically coupled to the input surface. The optical interface is configured to (i) receive the emitted light from the scintillator and (ii) output, via the output surface, output light. An optical interface refractive index substantially equals a scintillator refractive index.

Abstract: Methods and apparatus to perform wavefront analysis, including phase and amplitude information, and 3D measurements in optical systems, and in particular those based on analyzing the output of an intermediate plane, such as an image plane, of an optical system. Measurement of surface topography in the presence of thin film coatings, or of the individual layers of a multilayered structure is described. Multi-wavelength analysis in combination with phase and amplitude mapping is utilized. Methods of improving phase and surface topography measurements by wavefront propagation and refocusing, using virtual wavefront propagation based on solutions of Maxwell's equations are described. Reduction of coherence noise in optical imaging systems is achieved by such phase manipulation methods, or by methods utilizing a combination of wideband and coherent sources.

Abstract: Methods and apparatus to perform wavefront analysis, including phase and amplitude information, and 3D measurements in optical systems, and in particular those based on analyzing the output of an intermediate plane, such as an image plane, of an optical system. Measurement of surface topography in the presence of thin film coatings, or of the individual layers of a multilayered structure is described. Multi-wavelength analysis in combination with phase and amplitude mapping is utilized. Methods of improving phase and surface topography measurements by wavefront propagation and refocusing, using virtual wavefront propagation based on solutions of Maxwell's equations are described. Reduction of coherence noise in optical imaging systems is achieved by such phase manipulation methods, or by methods utilizing a combination of wideband and coherent sources.

Abstract: A cascaded image intensifier device is presented. In one embodiment the device comprises: at least two sections in cascade, each of a first section and a last section out of the at least two sections including a photocathode unit adapted to convert photons to electrons and a screen unit adapted to convert electrons to photons; wherein the first section includes a reducing element adapted to: (i) reduce ion-caused degradation of a photocathode unit of the first section, and (ii) reduce a number of photons exiting from the first section from a first value to a second value; and wherein the last section outputs a number of photons that equals or exceeds the first value. Also disclosed are methods and systems using the disclosed cascaded image intensifier device.

Abstract: A cascaded image intensifier device is presented. In one embodiment the device comprises: at least two sections in cascade, each of a first section and a last section out of the at least two sections including a photocathode unit adapted to convert photons to electrons and a screen unit adapted to convert electrons to photons; wherein the first section includes a reducing element adapted to: (i) reduce ion-caused degradation of a photocathode unit of the first section, and (ii) reduce a number of photons exiting from the first section from a first value to a second value; and wherein the last section outputs a number of photons that equals or exceeds the first value. Also disclosed are methods and systems using the disclosed cascaded image intensifier device.

Abstract: A detachably coupled image intensifier and image sensor combination is disclosed along with systems and methods for using the detachably coupled image intensifier and image sensor combination. In one embodiment, there are at least two fiber optic plates aligned between the image intensifier and image sensor, and an oil or a gel is used to fill some or all of the gap(s) between pair(s) of adjacent fiber optic plates. In one embodiment, the detachably coupled image intensifier and image sensor combination is used for sample inspection.

Abstract: An image intensifier device includes a photocathode unit having an active region adapted to convert light to electrons; a luminescent screen unit adapted to convert electrons emitted from the photocathode unit to light while generating ions; and a charge particle control unit. The latter is adapted to direct electrons from the photocathode unit towards the luminescent screen unit while substantially preventing the generated ions to reach at least the active region of the photocathode unit.