Abstract: A method, an inspection system and a sensing unit. The sensing unit may include a light recycling optics and a photon to electron converter. The photon to electron converter is configured to receive a first light beam emitted from the object and impinging on the partially reflective surface at a first oblique angle, absorb a first portion and reflect a second portion of the first light beam to provide a first reflected beam. The light recycling optics is configured to redirect, towards the partially reflective surface, one or more reflected beams reflected from the partially reflective surface to provide one or more recycled beams. The photon to electron converter is configured to output electrons that represents an absorbed portion of the input light beam and an absorbed portion of each one of the one or more recycled beam.

Abstract: A method, an inspection system and a sensing unit. The sensing unit may include a light recycling optics and a photon to electron converter. The photon to electron converter is configured to receive a first light beam emitted from the object and impinging on the partially reflective surface at a first oblique angle, absorb a first portion and reflect a second portion of the first light beam to provide a first reflected beam. The light recycling optics is configured to redirect, towards the partially reflective surface, one or more reflected beams reflected from the partially reflective surface to provide one or more recycled beams. The photon to electron converter is configured to output electrons that represents an absorbed portion of the input light beam and an absorbed portion of each one of the one or more recycled beam.

Abstract: A method for controlling an avalanche photo diode (APD) and a device that includes a high gain stable APD. The device may include an APD, a compensation circuit that comprises a compensation component that is thermally coupled to the APD, a temperature control module having a part that is thermally coupled to the compensation component and to the APD, and one or more additional components. The APD is formed within a first semiconductor epitaxial layer that is grown on a first side of a substrate, the substrate is highly thermally conductive and electrically insulating.

Abstract: A method, an inspection system and a sensing unit. The sensing unit may include a light recycling optics and a photon to electron converter. The photon to electron converter is configured to receive a first light beam emitted from the object and impinging on the partially reflective surface at a first oblique angle, absorb a first portion and reflect a second portion of the first light beam to provide a first reflected beam. The light recycling optics is configured to redirect, towards the partially reflective surface, one or more reflected beams reflected from the partially reflective surface to provide one or more recycled beams. The photon to electron converter is configured to output electrons that represents an absorbed portion of the input light beam and an absorbed portion of each one of the one or more recycled beam.

Abstract: There may be provided detection circuit that may include (i) a photodiode that may be configured to convert radiation to a photodiode electrical signal; (ii) a photodiode bias circuit that may be configured to bias the photodiode, wherein the photodiode bias circuit may include a photodiode bias voltage supply and a photodiode bias capacitor; and (iii) a differential transimpedance amplifier that may be configured to amplify the photodiode electrical signal to provide a differential voltage. The differential transimpedance amplifier may include an amplification circuit and an additional circuit, wherein the amplification circuit may include a positive input port, a negative input port, a positive output port, a negative output port and a common mode input port. The photodiode bias voltage supply may be a floating voltage supply.

Abstract: A method and a detection circuit. The detection circuit may include (a) a photodiode that is configured to convert radiation to a photodiode current; (b) a photodiode bias circuit that is configured to bias the photodiode; (c) a dynamic resistance circuit that has a first terminal and a second terminal; (d) a transimpedance amplifier that is configured to amplify an output current of the dynamic resistance circuit to provide an output voltage, wherein the second terminal is coupled to a negative input port of the amplification circuit; and (e) a conductor that is coupled between the first terminal and an anode of the photodiode.

Abstract: A detection circuit that may include (i) a photosensor that is configured to convert light to current; wherein the photosensor has an output node and is configured to operate as a current source, (ii) an adder, and (iii) multiple amplification branches that are coupled in parallel between the adder and the output node of the photosensor. The multiple amplification branches do not share a feedback circuit, wherein all amplification branches of the multiple amplification branches comprise an amplifier of a same type, wherein the type is selected out of a transimpedance amplifier and a current amplifier.

Abstract: A method for controlling an avalanche photo diode (APD) and a device that includes a high gain stable APD. The device may include an APD, a compensation circuit that comprises a compensation component that is thermally coupled to the APD, a temperature control module having a part that is thermally coupled to the compensation component and to the APD, and one or more additional components. The APD is formed within a first semiconductor epitaxial layer that is grown on a first side of a substrate, the substrate is highly thermally conductive and electrically insulating.

Abstract: A device and method for detecting radiation comprising: a radiation-sensitive surface composed of an array of electrically inter-isolated radiation-sensitive elements (e.g. avalanche photodiode (APD), PIN diode, or scintillation sensor), each radiation-sensitive element is adapted to generate an electric current in response to absorbing radiation; an array of conversion circuits, each conversion circuit electrically coupled to a respective radiation-sensitive element and configured to generate an output signal indicative of the current generated by the radiation-sensitive element coupled thereto; and one or more summation arrangements, each summation arrangement coupled to a respective group of the conversion circuits, and configured to produce a summation result indicative of the radiation absorbed by respective group of the conversion circuits. The radiation-sensitive surface may be shaped as a dome-shape surface.

Abstract: A supply unit for driving an electrode of a charged particle beam column, the supply unit includes a first amplifier and a second amplifier that are configured to receive an input signal, an output of the first amplifier is coupled, via the first resistor, to a signal line of the coaxial cable, an output of the second amplifier is coupled, via the second resistor, to a main shield of the coaxial cable, one port of the first amplifier and one port of the second amplifier are coupled to a power supply return port. The signal line is configured to provide a first driving signal to an that is coupled between the signal line and the power supply return port.

Abstract: A detection circuit that may include (i) a photosensor that is configured to convert light to current; wherein the photosensor has an output node and is configured to operate as a current source, (ii) an adder, and (iii) multiple amplification branches that are coupled in parallel between the adder and the output node of the photosensor. The multiple amplification branches do not share a feedback circuit, wherein all amplification branches of the multiple amplification branches comprise an amplifier of a same type, wherein the type is selected out of a transimpedance amplifier and a current amplifier.

Abstract: A detection circuit that may include a solid state photosensor that may include a junction, a controller, and a measurement circuit. The measurement circuit is configured to generate a measurement result that is indicative of a temperature of the junction during a curing period of the solid state photosensor. The controller is configured to control, during the curing period, the temperature of the junction, based on the measurement result.

Abstract: There may be provided detection circuit that may include (i) a photodiode that may be configured to convert radiation to a photodiode electrical signal; (ii) a photodiode bias circuit that may be configured to bias the photodiode, wherein the photodiode bias circuit may include a photodiode bias voltage supply and a photodiode bias capacitor; and (iii) a differential transimpedance amplifier that may be configured to amplify the photodiode electrical signal to provide a differential voltage. The differential transimpedance amplifier may include an amplification circuit and an additional circuit, wherein the amplification circuit may include a positive input port, a negative input port, a positive output port, a negative output port and a common mode input port. The photodiode bias voltage supply may be a floating voltage supply.

Abstract: A method and a detection circuit. The detection circuit may include (a) a photodiode that is configured to convert radiation to a photodiode current; (b) a photodiode bias circuit that is configured to bias the photodiode; (c) a dynamic resistance circuit that has a first terminal and a second terminal; (d) a transimpedance amplifier that is configured to amplify an output current of the dynamic resistance circuit to provide an output voltage, wherein the second terminal is coupled to a negative input port of the amplification circuit; and (e) a conductor that is coupled between the first terminal and an anode of the photodiode.

Abstract: A method, an inspection system and a sensing unit. The sensing unit may include a light recycling optics and a photon to electron converter. The photon to electron converter is configured to receive a first light beam emitted from the object and impinging on the partially reflective surface at a first oblique angle, absorb a first portion and reflect a second portion of the first light beam to provide a first reflected beam. The light recycling optics is configured to redirect, towards the partially reflective surface, one or more reflected beams reflected from the partially reflective surface to provide one or more recycled beams. The photon to electron converter is configured to output electrons that represents an absorbed portion of the input light beam and an absorbed portion of each one of the one or more recycled beam.

Abstract: A sensing unit includes a first set of sensors that comprises a first set of active areas that are surrounded by a first set of first non-active areas and a second set of sensors that comprises a second set of active areas that are surrounded by a second set of non-active areas. The first set of sensors and the second set of sensors are positioned at different heights, the first set of active areas and the second set of active areas do not overlap, and the first set of non-active areas and the second set of non-active areas partially overlap.

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 method for scanning an object with a charged particle beam, the method may include repeating, for each pair of scan lines out of multiple pairs of scan lines, the stages of: (i) deflecting the charged particle beam along a first direction, thereby scanning the object along a first scan line of the pair of scan lines; (ii) collecting electrons emitted from the object during the scanning of the object along a majority of the first scan line; (iii) deflecting the charged particle beam along a second direction that is normal to the first direction; (iv) deflecting the charged particle beam along a third direction that is opposite to the first direction, thereby scanning the object along a second scan line of the pair of scan lines; (v) collecting electrons emitted from the object during the scanning of the object along a majority of the second scan line; and (vi) deflecting the charged particle beam along the second direction that is normal to the third direction.

Abstract: A device that may include a DC power supply coupled to a fixed current source; an APD; a DC voltage regulator that comprises a regulating transistor, arranged to maintain a regulated voltage at a fixed value over different APD currents; a temperature control module that is arranged to maintain a portion of the temperature control module at a fixed temperature; and compensation circuit that comprises a compensation component that is thermally coupled to the APD. A voltage drop over the compensation component is smaller than a voltage drop over the APD. A sum of (a) a current that pass through the APD and (b) a current that passes through the compensation component is fixed. The portion of the temperature control module is thermally coupled to the compensation component and to the APD.

Abstract: A method for scanning an object with a charged particle beam, the method may include repeating, for each pair of scan lines out of multiple pairs of scan lines, the stages of: (i) deflecting the charged particle beam along a first direction, thereby scanning the object along a first scan line of the pair of scan lines; (ii) collecting electrons emitted from the object during the scanning of the object along a majority of the first scan line; (iii) deflecting the charged particle beam along a second direction that is normal to the first direction; (iv) deflecting the charged particle beam along a third direction that is opposite to the first direction, thereby scanning the object along a second scan line of the pair of scan lines; (v) collecting electrons emitted from the object during the scanning of the object along a majority of the second scan line; and (vi) deflecting the charged particle beam along the second direction that is normal to the third direction.